CVE-2026-52991

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-52991", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.377Z", "datePublished": "2026-06-24T16:29:04.810Z", "dateUpdated": "2026-10-30T12:26:24.799Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:26:24.799Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/psi: fix race between file release and pressure write\n\nA potential race condition exists between pressure write and cgroup file\nrelease regarding the priv member of struct kernfs_open_file, which\ntriggers the uaf reported in [1].\n\nConsider the following scenario involving execution on two separate CPUs:\n\n CPU0\t\t\t\t\tCPU1\n ====\t\t\t\t\t====\n\t\t\t\t\tvfs_rmdir()\n\t\t\t\t\tkernfs_iop_rmdir()\n\t\t\t\t\tcgroup_rmdir()\n\t\t\t\t\tcgroup_kn_lock_live()\n\t\t\t\t\tcgroup_destroy_locked()\n\t\t\t\t\tcgroup_addrm_files()\n\t\t\t\t\tcgroup_rm_file()\n\t\t\t\t\tkernfs_remove_by_name()\n\t\t\t\t\tkernfs_remove_by_name_ns()\n vfs_write()\t\t\t\t__kernfs_remove()\n new_sync_write()\t\t\tkernfs_drain()\n kernfs_fop_write_iter()\t\tkernfs_drain_open_files()\n cgroup_file_write()\t\t\tkernfs_release_file()\n pressure_write()\t\t\tcgroup_file_release()\n ctx = of->priv;\n\t\t\t\t\tkfree(ctx);\n \t\t\t\t\tof->priv = NULL;\n\t\t\t\t\tcgroup_kn_unlock()\n cgroup_kn_lock_live()\n cgroup_get(cgrp)\n cgroup_kn_unlock()\n if (ctx->psi.trigger) // here, trigger uaf for ctx, that is of->priv\n\nThe cgroup_rmdir() is protected by the cgroup_mutex, it also safeguards\nthe memory deallocation of of->priv performed within cgroup_file_release().\nHowever, the operations involving of->priv executed within pressure_write()\nare not entirely covered by the protection of cgroup_mutex. Consequently,\nif the code in pressure_write(), specifically the section handling the\nctx variable executes after cgroup_file_release() has completed, a uaf\nvulnerability involving of->priv is triggered.\n\nTherefore, the issue can be resolved by extending the scope of the\ncgroup_mutex lock within pressure_write() to encompass all code paths\ninvolving of->priv, thereby properly synchronizing the race condition\noccurring between cgroup_file_release() and pressure_write().\n\nAnd, if an live kn lock can be successfully acquired while executing\nthe pressure write operation, it indicates that the cgroup deletion\nprocess has not yet reached its final stage; consequently, the priv\npointer within open_file cannot be NULL. Therefore, the operation to\nretrieve the ctx value must be moved to a point *after* the live kn\nlock has been successfully acquired.\n\nIn another situation, specifically after entering cgroup_kn_lock_live()\nbut before acquiring cgroup_mutex, there exists a different class of\nrace condition:\n\nCPU0: write memory.pressure CPU1: write cgroup.pressure=0\n===========================\t\t =============================\n\nkernfs_fop_write_iter()\n kernfs_get_active_of(of)\n pressure_write()\n cgroup_kn_lock_live(memory.pressure)\n cgroup_tryget(cgrp)\n kernfs_break_active_protection(kn)\n ... blocks on cgroup_mutex\n\n \t cgroup_pressure_write()\n \t cgroup_kn_lock_live(cgroup.pressure)\n \t cgroup_file_show(memory.pressure, false)\n \t kernfs_show(false)\n \t kernfs_drain_open_files()\n \t cgroup_file_release(of)\n \t kfree(ctx)\n \t of->priv = NULL\n \t cgroup_kn_unlock()\n\n ... acquires cgroup_mutex\n ctx = of->priv; // may now be NULL\n if (ctx->psi.trigger) // NULL dereference\n\nConsequently, there is a possibility that of->priv is NULL, the pressure\nwrite needs to check for this.\n\nNow that the scope of the cgroup_mutex has been expanded, the original\nexplicit cgroup_get/put operations are no longer necessary, this is\nbecause acquiring/releasing the live kn lock inherently executes a\ncgroup get/put operation.\n\n[1]\nBUG: KASAN: slab-use-after-free in pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\nCall Trace:\n pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\n cgroup_file_write+0x36f/0x790 kernel/cgroup/cgroup.c:43\n---truncated---"}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerable path is reached through local syscalls writing to cgroup v2 PSI control files such as cpu.pressure, memory.pressure, io.pressure, or irq.pressure. There is no network or physical packet-processing path involved.\nAC:L - The attacker can control both sides of the race by concurrently writing a pressure trigger and removing the cgroup or disabling cgroup.pressure to drain open files. No unusual victim state or externally uncontrolled timing condition is required beyond a repeatable local race.\nPR:L - The pressure files are local cgroupfs files; root can always reach them, and unprivileged users can reach equivalent files in delegated cgroup sub-hierarchies they can create and manage. This is therefore low local privilege rather than init-namespace administrator-only.\nUI:N - Exploitation only requires attacker-controlled syscalls against cgroupfs file descriptors. No victim user action is needed.\nS:U - The vulnerability corrupts kernel memory from a kernel cgroup/PSI file operation and impacts the same kernel security authority. It is not a VM escape, IOMMU bypass, or cross-authority boundary violation.\nC:H - This is a slab use-after-free of struct cgroup_file_ctx, and the stale object can be raced with attacker-influenced heap reuse. Following kernel UAF scoring guidance, this can plausibly support kernel memory disclosure primitives.\nI:H - The pre-fix path can read and later store through the freed ctx->psi.trigger field after the object has been freed, giving a plausible write/corruption primitive with heap grooming. Following kernel UAF scoring guidance, integrity impact is high.\nA:H - The reported bug is a KASAN slab-use-after-free in pressure_write and can crash or oops the kernel. Repeated local triggering can therefore cause high availability impact."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/cgroup/cgroup.c"], "versions": [{"version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "58e6ca11e45c9d6e52255d1135e7dbff0a360334", "status": "affected", "versionType": "git"}, {"version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "d8ddbc3330fa6851c56b046e630a8fc64830a0ce", "status": "affected", "versionType": "git"}, {"version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "af0638534bfae7980582c6482531a0872f8ee341", "status": "affected", "versionType": "git"}, {"version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "03dc070fa0fc3cb4068693f468ccd5f8a7e58282", "status": "affected", "versionType": "git"}, {"version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "d4352c0709bfd38c752fccbde7fd72a82ac78f23", "status": "affected", "versionType": "git"}, {"version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "a5b98009f16d8a5fb4a8ff9a193f5735515c38fa", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/cgroup/cgroup.c"], "versions": [{"version": "5.2", "status": "affected"}, {"version": "0", "lessThan": "5.2", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.191", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.114", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.33", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0.10", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.2", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.2", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.2", "versionEndExcluding": "6.12.114"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.2", "versionEndExcluding": "6.18.33"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.2", "versionEndExcluding": "7.0.10"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.2", "versionEndExcluding": "7.1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/58e6ca11e45c9d6e52255d1135e7dbff0a360334"}, {"url": "https://git.kernel.org/stable/c/d8ddbc3330fa6851c56b046e630a8fc64830a0ce"}, {"url": "https://git.kernel.org/stable/c/af0638534bfae7980582c6482531a0872f8ee341"}, {"url": "https://git.kernel.org/stable/c/03dc070fa0fc3cb4068693f468ccd5f8a7e58282"}, {"url": "https://git.kernel.org/stable/c/d4352c0709bfd38c752fccbde7fd72a82ac78f23"}, {"url": "https://git.kernel.org/stable/c/a5b98009f16d8a5fb4a8ff9a193f5735515c38fa"}], "title": "sched/psi: fix race between file release and pressure write", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"affected": [{"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:10"], "defaultStatus": 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A race condition exists between the file release and pressure write operations, specifically concerning the `priv` member of `struct kernfs_open_file`. This can lead to a use-after-free vulnerability or a NULL dereference, potentially causing system instability or a denial of service. The issue arises when the `priv` member is deallocated during a cgroup file release while a pressure write operation attempts to access it, or when it becomes NULL before being accessed."}], "metrics": [{"other": {"content": {"namespace": "https://access.redhat.com/security/updates/classification/", "value": "Important"}, "type": "Red Hat severity rating"}}, {"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "format": "CVSS"}], "problemTypes": [{"descriptions": [{"cweId": "CWE-367", "description": "Time-of-check Time-of-use (TOCTOU) Race Condition", "lang": "en", "type": "CWE"}]}], "references": [{"tags": ["vdb-entry", "x_refsource_REDHAT"], "url": "https://access.redhat.com/security/cve/CVE-2026-52991"}, {"name": "RHBZ#2492403", "tags": ["issue-tracking", "x_refsource_REDHAT"], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2492403"}, {"tags": ["x_sadp-csaf-vex"], "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52991.json"}, {"tags": ["vendor-advisory", "x_refsource_REDHAT"], "url": "https://access.redhat.com/errata/RHSA-2026:57251"}, {"tags": ["vendor-advisory", "x_refsource_REDHAT"], "url": "https://access.redhat.com/errata/RHSA-2026:57252"}, {"tags": ["vendor-advisory", "x_refsource_REDHAT"], "url": "https://access.redhat.com/errata/RHSA-2026:57253"}, {"tags": ["vendor-advisory", "x_refsource_REDHAT"], "url": "https://access.redhat.com/errata/RHSA-2026:57254"}], "solutions": [{"lang": "en", "value": "RHSA-2026:57251: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10), Red Hat Enterprise Linux Real Time (v. 10), Red Hat Enterprise Linux Real Time for NFV (v. 10)"}, {"lang": "en", "value": "RHSA-2026:57252: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9), Red Hat Enterprise Linux Real Time (v. 9), Red Hat Enterprise Linux Real Time for NFV (v. 9)"}, {"lang": "en", "value": "RHSA-2026:57253: Red Hat Enterprise Linux BaseOS (v. 8), Red Hat Enterprise Linux CRB (v. 8)"}, {"lang": "en", "value": "RHSA-2026:57254: Red Hat Enterprise Linux NFV (v. 8), Red Hat Enterprise Linux RT (v. 8)"}], "timeline": [{"lang": "en", "time": "2026-06-24T00:00:00.000Z", "value": "Reported to Red Hat."}, {"lang": "en", "time": "2026-06-24T00:00:00.000Z", "value": "Made public."}], "title": "kernel: sched/psi: fix race between file release and pressure write", "x_adpType": "supplier", "x_generator": {"engine": "sadp-cli 1.0.0"}, "providerMetadata": {"orgId": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "shortName": "redhat-SADP", "dateUpdated": "2026-08-20T12:31:57.785Z"}}, {"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-52991", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T15:24:15.317006Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-367", "description": "CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition"}]}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-19T19:47:12.396Z"}}]}}

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The issue arises when the `priv` member is deallocated during a cgroup file release while a pressure write operation attempts to access it, or when it becomes NULL before being accessed."}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-367", "description": "Time-of-check Time-of-use (TOCTOU) Race Condition"}]}], "providerMetadata": {"orgId": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "shortName": "redhat-SADP", "dateUpdated": "2026-08-20T12:31:57.785Z"}}, {"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-52991", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T15:24:15.317006Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-367", "description": "CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition"}]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T15:24:16.340Z"}}], "cna": {"title": "sched/psi: fix race between file release and pressure write", "metrics": [{"cvssV3_1": {"version": "3.1", "baseScore": 7.8, "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerable path is reached through local syscalls writing to cgroup v2 PSI control files such as cpu.pressure, memory.pressure, io.pressure, or irq.pressure. There is no network or physical packet-processing path involved.\nAC:L - The attacker can control both sides of the race by concurrently writing a pressure trigger and removing the cgroup or disabling cgroup.pressure to drain open files. No unusual victim state or externally uncontrolled timing condition is required beyond a repeatable local race.\nPR:L - The pressure files are local cgroupfs files; root can always reach them, and unprivileged users can reach equivalent files in delegated cgroup sub-hierarchies they can create and manage. This is therefore low local privilege rather than init-namespace administrator-only.\nUI:N - Exploitation only requires attacker-controlled syscalls against cgroupfs file descriptors. No victim user action is needed.\nS:U - The vulnerability corrupts kernel memory from a kernel cgroup/PSI file operation and impacts the same kernel security authority. It is not a VM escape, IOMMU bypass, or cross-authority boundary violation.\nC:H - This is a slab use-after-free of struct cgroup_file_ctx, and the stale object can be raced with attacker-influenced heap reuse. Following kernel UAF scoring guidance, this can plausibly support kernel memory disclosure primitives.\nI:H - The pre-fix path can read and later store through the freed ctx->psi.trigger field after the object has been freed, giving a plausible write/corruption primitive with heap grooming. Following kernel UAF scoring guidance, integrity impact is high.\nA:H - The reported bug is a KASAN slab-use-after-free in pressure_write and can crash or oops the kernel. Repeated local triggering can therefore cause high availability impact."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "58e6ca11e45c9d6e52255d1135e7dbff0a360334", "versionType": "git"}, {"status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "d8ddbc3330fa6851c56b046e630a8fc64830a0ce", "versionType": "git"}, {"status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "af0638534bfae7980582c6482531a0872f8ee341", "versionType": "git"}, {"status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "03dc070fa0fc3cb4068693f468ccd5f8a7e58282", "versionType": "git"}, {"status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "d4352c0709bfd38c752fccbde7fd72a82ac78f23", "versionType": "git"}, {"status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "lessThan": "a5b98009f16d8a5fb4a8ff9a193f5735515c38fa", "versionType": "git"}], "programFiles": ["kernel/cgroup/cgroup.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.2"}, {"status": "unaffected", "version": "0", "lessThan": "5.2", "versionType": "semver"}, {"status": "unaffected", "version": "6.1.191", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.160", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.114", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.33", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.0.10", "versionType": "semver", "lessThanOrEqual": "7.0.*"}, {"status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["kernel/cgroup/cgroup.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/58e6ca11e45c9d6e52255d1135e7dbff0a360334"}, {"url": "https://git.kernel.org/stable/c/d8ddbc3330fa6851c56b046e630a8fc64830a0ce"}, {"url": "https://git.kernel.org/stable/c/af0638534bfae7980582c6482531a0872f8ee341"}, {"url": "https://git.kernel.org/stable/c/03dc070fa0fc3cb4068693f468ccd5f8a7e58282"}, {"url": "https://git.kernel.org/stable/c/d4352c0709bfd38c752fccbde7fd72a82ac78f23"}, {"url": "https://git.kernel.org/stable/c/a5b98009f16d8a5fb4a8ff9a193f5735515c38fa"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/psi: fix race between file release and pressure write\n\nA potential race condition exists between pressure write and cgroup file\nrelease regarding the priv member of struct kernfs_open_file, which\ntriggers the uaf reported in [1].\n\nConsider the following scenario involving execution on two separate CPUs:\n\n CPU0\t\t\t\t\tCPU1\n ====\t\t\t\t\t====\n\t\t\t\t\tvfs_rmdir()\n\t\t\t\t\tkernfs_iop_rmdir()\n\t\t\t\t\tcgroup_rmdir()\n\t\t\t\t\tcgroup_kn_lock_live()\n\t\t\t\t\tcgroup_destroy_locked()\n\t\t\t\t\tcgroup_addrm_files()\n\t\t\t\t\tcgroup_rm_file()\n\t\t\t\t\tkernfs_remove_by_name()\n\t\t\t\t\tkernfs_remove_by_name_ns()\n vfs_write()\t\t\t\t__kernfs_remove()\n new_sync_write()\t\t\tkernfs_drain()\n kernfs_fop_write_iter()\t\tkernfs_drain_open_files()\n cgroup_file_write()\t\t\tkernfs_release_file()\n pressure_write()\t\t\tcgroup_file_release()\n ctx = of->priv;\n\t\t\t\t\tkfree(ctx);\n \t\t\t\t\tof->priv = NULL;\n\t\t\t\t\tcgroup_kn_unlock()\n cgroup_kn_lock_live()\n cgroup_get(cgrp)\n cgroup_kn_unlock()\n if (ctx->psi.trigger) // here, trigger uaf for ctx, that is of->priv\n\nThe cgroup_rmdir() is protected by the cgroup_mutex, it also safeguards\nthe memory deallocation of of->priv performed within cgroup_file_release().\nHowever, the operations involving of->priv executed within pressure_write()\nare not entirely covered by the protection of cgroup_mutex. Consequently,\nif the code in pressure_write(), specifically the section handling the\nctx variable executes after cgroup_file_release() has completed, a uaf\nvulnerability involving of->priv is triggered.\n\nTherefore, the issue can be resolved by extending the scope of the\ncgroup_mutex lock within pressure_write() to encompass all code paths\ninvolving of->priv, thereby properly synchronizing the race condition\noccurring between cgroup_file_release() and pressure_write().\n\nAnd, if an live kn lock can be successfully acquired while executing\nthe pressure write operation, it indicates that the cgroup deletion\nprocess has not yet reached its final stage; consequently, the priv\npointer within open_file cannot be NULL. Therefore, the operation to\nretrieve the ctx value must be moved to a point *after* the live kn\nlock has been successfully acquired.\n\nIn another situation, specifically after entering cgroup_kn_lock_live()\nbut before acquiring cgroup_mutex, there exists a different class of\nrace condition:\n\nCPU0: write memory.pressure CPU1: write cgroup.pressure=0\n===========================\t\t =============================\n\nkernfs_fop_write_iter()\n kernfs_get_active_of(of)\n pressure_write()\n cgroup_kn_lock_live(memory.pressure)\n cgroup_tryget(cgrp)\n kernfs_break_active_protection(kn)\n ... blocks on cgroup_mutex\n\n \t cgroup_pressure_write()\n \t cgroup_kn_lock_live(cgroup.pressure)\n \t cgroup_file_show(memory.pressure, false)\n \t kernfs_show(false)\n \t kernfs_drain_open_files()\n \t cgroup_file_release(of)\n \t kfree(ctx)\n \t of->priv = NULL\n \t cgroup_kn_unlock()\n\n ... acquires cgroup_mutex\n ctx = of->priv; // may now be NULL\n if (ctx->psi.trigger) // NULL dereference\n\nConsequently, there is a possibility that of->priv is NULL, the pressure\nwrite needs to check for this.\n\nNow that the scope of the cgroup_mutex has been expanded, the original\nexplicit cgroup_get/put operations are no longer necessary, this is\nbecause acquiring/releasing the live kn lock inherently executes a\ncgroup get/put operation.\n\n[1]\nBUG: KASAN: slab-use-after-free in pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\nCall Trace:\n pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\n cgroup_file_write+0x36f/0x790 kernel/cgroup/cgroup.c:43\n---truncated---"}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.191", "versionStartIncluding": "5.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.160", "versionStartIncluding": "5.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.114", "versionStartIncluding": "5.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.18.33", "versionStartIncluding": "5.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.0.10", "versionStartIncluding": "5.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.1", "versionStartIncluding": "5.2"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:26:24.799Z"}}}, "cveMetadata": {"cveId": "CVE-2026-52991", "state": "PUBLISHED", "dateUpdated": "2026-10-30T12:26:24.799Z", "dateReserved": "2026-06-09T07:44:35.377Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2026-06-24T16:29:04.810Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/cgroup/cgroup.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "58e6ca11e45c9d6e52255d1135e7dbff0a360334", "status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "versionType": "git"}, {"lessThan": "d8ddbc3330fa6851c56b046e630a8fc64830a0ce", "status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "versionType": "git"}, {"lessThan": "af0638534bfae7980582c6482531a0872f8ee341", "status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "versionType": "git"}, {"lessThan": "03dc070fa0fc3cb4068693f468ccd5f8a7e58282", "status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "versionType": "git"}, {"lessThan": "d4352c0709bfd38c752fccbde7fd72a82ac78f23", "status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "versionType": "git"}, {"lessThan": "a5b98009f16d8a5fb4a8ff9a193f5735515c38fa", "status": "affected", "version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/cgroup/cgroup.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.2"}, {"lessThan": "5.2", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.160", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.114", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.33", "versionType": "semver"}, {"lessThanOrEqual": "7.0.*", "status": "unaffected", "version": "7.0.10", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"affectedData": [{"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:10"], "defaultStatus": "affected", "packageName": "kernel", "product": "Red Hat Enterprise Linux 10", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:6"], "defaultStatus": "unaffected", "packageName": "kernel", "product": "Red Hat Enterprise Linux 6", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:7"], "defaultStatus": "unaffected", "packageName": "kernel", "product": "Red Hat Enterprise Linux 7", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:7"], "defaultStatus": "unaffected", "packageName": "kernel-rt", "product": "Red Hat Enterprise Linux 7", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:8"], "defaultStatus": "affected", "packageName": "kernel", "product": "Red Hat Enterprise Linux 8", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:8"], "defaultStatus": "affected", "packageName": "kernel-rt", "product": "Red Hat Enterprise Linux 8", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:9"], "defaultStatus": "affected", "packageName": "kernel", "product": "Red Hat Enterprise Linux 9", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:9"], "defaultStatus": "affected", "packageName": "kernel-rt", "product": "Red Hat Enterprise Linux 9", "vendor": "Red Hat"}], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "E61720BB-33AA-4F7D-842F-6F12F9E9FD8C", "versionEndExcluding": "6.18.33", "versionStartIncluding": "5.2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "A13475D2-59BF-4716-94B5-7C1D239A2CF4", "versionEndExcluding": "7.0.10", "versionStartIncluding": "6.19", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*", "matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/psi: fix race between file release and pressure write\n\nA potential race condition exists between pressure write and cgroup file\nrelease regarding the priv member of struct kernfs_open_file, which\ntriggers the uaf reported in [1].\n\nConsider the following scenario involving execution on two separate CPUs:\n\n CPU0\t\t\t\t\tCPU1\n ====\t\t\t\t\t====\n\t\t\t\t\tvfs_rmdir()\n\t\t\t\t\tkernfs_iop_rmdir()\n\t\t\t\t\tcgroup_rmdir()\n\t\t\t\t\tcgroup_kn_lock_live()\n\t\t\t\t\tcgroup_destroy_locked()\n\t\t\t\t\tcgroup_addrm_files()\n\t\t\t\t\tcgroup_rm_file()\n\t\t\t\t\tkernfs_remove_by_name()\n\t\t\t\t\tkernfs_remove_by_name_ns()\n vfs_write()\t\t\t\t__kernfs_remove()\n new_sync_write()\t\t\tkernfs_drain()\n kernfs_fop_write_iter()\t\tkernfs_drain_open_files()\n cgroup_file_write()\t\t\tkernfs_release_file()\n pressure_write()\t\t\tcgroup_file_release()\n ctx = of->priv;\n\t\t\t\t\tkfree(ctx);\n \t\t\t\t\tof->priv = NULL;\n\t\t\t\t\tcgroup_kn_unlock()\n cgroup_kn_lock_live()\n cgroup_get(cgrp)\n cgroup_kn_unlock()\n if (ctx->psi.trigger) // here, trigger uaf for ctx, that is of->priv\n\nThe cgroup_rmdir() is protected by the cgroup_mutex, it also safeguards\nthe memory deallocation of of->priv performed within cgroup_file_release().\nHowever, the operations involving of->priv executed within pressure_write()\nare not entirely covered by the protection of cgroup_mutex. Consequently,\nif the code in pressure_write(), specifically the section handling the\nctx variable executes after cgroup_file_release() has completed, a uaf\nvulnerability involving of->priv is triggered.\n\nTherefore, the issue can be resolved by extending the scope of the\ncgroup_mutex lock within pressure_write() to encompass all code paths\ninvolving of->priv, thereby properly synchronizing the race condition\noccurring between cgroup_file_release() and pressure_write().\n\nAnd, if an live kn lock can be successfully acquired while executing\nthe pressure write operation, it indicates that the cgroup deletion\nprocess has not yet reached its final stage; consequently, the priv\npointer within open_file cannot be NULL. Therefore, the operation to\nretrieve the ctx value must be moved to a point *after* the live kn\nlock has been successfully acquired.\n\nIn another situation, specifically after entering cgroup_kn_lock_live()\nbut before acquiring cgroup_mutex, there exists a different class of\nrace condition:\n\nCPU0: write memory.pressure CPU1: write cgroup.pressure=0\n===========================\t\t =============================\n\nkernfs_fop_write_iter()\n kernfs_get_active_of(of)\n pressure_write()\n cgroup_kn_lock_live(memory.pressure)\n cgroup_tryget(cgrp)\n kernfs_break_active_protection(kn)\n ... blocks on cgroup_mutex\n\n \t cgroup_pressure_write()\n \t cgroup_kn_lock_live(cgroup.pressure)\n \t cgroup_file_show(memory.pressure, false)\n \t kernfs_show(false)\n \t kernfs_drain_open_files()\n \t cgroup_file_release(of)\n \t kfree(ctx)\n \t of->priv = NULL\n \t cgroup_kn_unlock()\n\n ... acquires cgroup_mutex\n ctx = of->priv; // may now be NULL\n if (ctx->psi.trigger) // NULL dereference\n\nConsequently, there is a possibility that of->priv is NULL, the pressure\nwrite needs to check for this.\n\nNow that the scope of the cgroup_mutex has been expanded, the original\nexplicit cgroup_get/put operations are no longer necessary, this is\nbecause acquiring/releasing the live kn lock inherently executes a\ncgroup get/put operation.\n\n[1]\nBUG: KASAN: slab-use-after-free in pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\nCall Trace:\n pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\n cgroup_file_write+0x36f/0x790 kernel/cgroup/cgroup.c:43\n---truncated---"}], "id": "CVE-2026-52991", "lastModified": "2026-10-30T13:19:05.697", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}, {"cvssData": {"attackComplexity": "HIGH", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.0, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.0, "impactScore": 5.9, "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-52991", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-16T15:24:15.317006Z", "version": "2.0.3"}}]}, "published": "2026-06-24T17:17:09.953", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/03dc070fa0fc3cb4068693f468ccd5f8a7e58282"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/58e6ca11e45c9d6e52255d1135e7dbff0a360334"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a5b98009f16d8a5fb4a8ff9a193f5735515c38fa"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/af0638534bfae7980582c6482531a0872f8ee341"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/d4352c0709bfd38c752fccbde7fd72a82ac78f23"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d8ddbc3330fa6851c56b046e630a8fc64830a0ce"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://access.redhat.com/errata/RHSA-2026:57251"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://access.redhat.com/errata/RHSA-2026:57252"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://access.redhat.com/errata/RHSA-2026:57253"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://access.redhat.com/errata/RHSA-2026:57254"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "tags": ["Third Party Advisory"], "url": "https://access.redhat.com/security/cve/CVE-2026-52991"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "tags": ["Issue Tracking", "Third Party Advisory"], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2492403"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "tags": ["Third Party Advisory"], "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52991.json"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-362"}], "source": "nvd@nist.gov", "type": "Primary"}, {"description": [{"lang": "en", "value": "CWE-367"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}, {"description": [{"lang": "en", "value": "CWE-367"}], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "type": "Secondary"}]}

{"bugzilla": {"description": "kernel: sched/psi: fix race between file release and pressure write", "id": "2492403", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2492403"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-367", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nsched/psi: fix race between file release and pressure write\nA potential race condition exists between pressure write and cgroup file\nrelease regarding the priv member of struct kernfs_open_file, which\ntriggers the uaf reported in [1].\nConsider the following scenario involving execution on two separate CPUs:\nCPU0CPU1\n========\nvfs_rmdir()\nkernfs_iop_rmdir()\ncgroup_rmdir()\ncgroup_kn_lock_live()\ncgroup_destroy_locked()\ncgroup_addrm_files()\ncgroup_rm_file()\nkernfs_remove_by_name()\nkernfs_remove_by_name_ns()\nvfs_write()__kernfs_remove()\nnew_sync_write()kernfs_drain()\nkernfs_fop_write_iter()kernfs_drain_open_files()\ncgroup_file_write()kernfs_release_file()\npressure_write()cgroup_file_release()\nctx = of->priv;\nkfree(ctx);\nof->priv = NULL;\ncgroup_kn_unlock()\ncgroup_kn_lock_live()\ncgroup_get(cgrp)\ncgroup_kn_unlock()\nif (ctx->psi.trigger) // here, trigger uaf for ctx, that is of->priv\nThe cgroup_rmdir() is protected by the cgroup_mutex, it also safeguards\nthe memory deallocation of of->priv performed within cgroup_file_release().\nHowever, the operations involving of->priv executed within pressure_write()\nare not entirely covered by the protection of cgroup_mutex. Consequently,\nif the code in pressure_write(), specifically the section handling the\nctx variable executes after cgroup_file_release() has completed, a uaf\nvulnerability involving of->priv is triggered.\nTherefore, the issue can be resolved by extending the scope of the\ncgroup_mutex lock within pressure_write() to encompass all code paths\ninvolving of->priv, thereby properly synchronizing the race condition\noccurring between cgroup_file_release() and pressure_write().\nAnd, if an live kn lock can be successfully acquired while executing\nthe pressure write operation, it indicates that the cgroup deletion\nprocess has not yet reached its final stage; consequently, the priv\npointer within open_file cannot be NULL. Therefore, the operation to\nretrieve the ctx value must be moved to a point *after* the live kn\nlock has been successfully acquired.\nIn another situation, specifically after entering cgroup_kn_lock_live()\nbut before acquiring cgroup_mutex, there exists a different class of\nrace condition:\nCPU0: write memory.pressure CPU1: write cgroup.pressure=0\n=========================== =============================\nkernfs_fop_write_iter()\nkernfs_get_active_of(of)\npressure_write()\ncgroup_kn_lock_live(memory.pressure)\ncgroup_tryget(cgrp)\nkernfs_break_active_protection(kn)\n... blocks on cgroup_mutex\ncgroup_pressure_write()\ncgroup_kn_lock_live(cgroup.pressure)\ncgroup_file_show(memory.pressure, false)\nkernfs_show(false)\nkernfs_drain_open_files()\ncgroup_file_release(of)\nkfree(ctx)\nof->priv = NULL\ncgroup_kn_unlock()\n... acquires cgroup_mutex\nctx = of->priv; // may now be NULL\nif (ctx->psi.trigger) // NULL dereference\nConsequently, there is a possibility that of->priv is NULL, the pressure\nwrite needs to check for this.\nNow that the scope of the cgroup_mutex has been expanded, the original\nexplicit cgroup_get/put operations are no longer necessary, this is\nbecause acquiring/releasing the live kn lock inherently executes a\ncgroup get/put operation.\n[1]\nBUG: KASAN: slab-use-after-free in pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\nCall Trace:\npressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011\ncgroup_file_write+0x36f/0x790 kernel/cgroup/cgroup.c:43\n---truncated---", "A flaw was found in the Linux kernel's Pressure Stall Information (PSI) subsystem. A race condition exists between the file release and pressure write operations, specifically concerning the `priv` member of `struct kernfs_open_file`. This can lead to a use-after-free vulnerability or a NULL dereference, potentially causing system instability or a denial of service. The issue arises when the `priv` member is deallocated during a cgroup file release while a pressure write operation attempts to access it, or when it becomes NULL before being accessed."], "name": "CVE-2026-52991", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-06-24T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-52991\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-52991\nhttps://lore.kernel.org/linux-cve-announce/2026062444-CVE-2026-52991-18fe@gregkh/T"], "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0e94682b73bfa6c44c98af7a26771c9c08c055d5,03dc070fa0fc3cb4068693f468ccd5f8a7e58282)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0e94682b73bfa6c44c98af7a26771c9c08c055d5,d4352c0709bfd38c752fccbde7fd72a82ac78f23)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0e94682b73bfa6c44c98af7a26771c9c08c055d5,a5b98009f16d8a5fb4a8ff9a193f5735515c38fa)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "5.2"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,5.2)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.33,6.18.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.0.10,7.0.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-06-24T21:00:11.772834+00:00", "updated": "2026-08-12T06:45:04.798780+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}