CVE-2026-74371

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-74371", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.889Z", "datePublished": "2026-08-15T05:58:51.610Z", "dateUpdated": "2026-09-14T11:58:45.047Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-09-14T11:58:45.047Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: fix BPF_PROG_QUERY OOB write and cgroup backward compat\n\nBPF_PROG_QUERY writes back the 'query.revision' field unconditionally to\nuserspace. If userspace passes a smaller 'bpf_attr' structure (e.g. 40\nbytes, which was the layout before the addition of 'query.revision'),\nthe kernel performs an out-of-bounds write.\n\nFix this by propagating the user-provided attribute size 'uattr_size'\ndown to the cgroup query handlers, and conditionally skipping writing\nthe revision field to userspace when the provided buffer size is\ninsufficient.\n\nquery.revision in bpf_mprog_query is structurally identical to the\ncgroup case: a late tail field, written unconditionally.\n\nBut the backward-compat hazard is not the same.\n\nThe min-historical-size test is per command, and bpf_mprog_query only\nserves attach types that were born with revision in the struct:\n\n- tcx_prog_query -> BPF_TCX_INGRESS/EGRESS\n- netkit_prog_query -> BPF_NETKIT_PRIMARY/PEER\n\ntcx, netkit, the revision field, and bpf_mprog_query itself all landed in\nthe same v6.6 merge window (053c8e1f235d added the mprog query API +\nrevision; tcx in e420bed02507, netkit in 35dfaad7188c). There has never\nbeen a tcx/netkit BPF_PROG_QUERY userspace that doesn't know about\nrevision. So for these commands the minimum legitimate struct already\ncovers offset 56-64 \u2014 no old binary can be broken here.\n\nContrast with cgroup: BPF_PROG_QUERY on cgroup attach types shipped in\n2017; revision write-back was bolted on years later (120933984460). That\npath has a real population of pre-revision callers."}], "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 flaw is reached only through the bpf(2) syscall BPF_PROG_QUERY command on cgroup attach types via __sys_bpf()\u2192bpf_prog_query()\u2192cgroup_bpf_prog_query(); per kernel CNA guidance BPF/tc/netlink paths are Local, not Network.\nAC:L - The attacker fully controls the bpf_attr buffer, its declared size (e.g. 40 bytes pre-revision), placement in memory, cgroup2 target_fd, and attach_type; passing a short size reliably triggers the 8-byte revision copy_to_user at offset 56 with no race or external precondition.\nPR:L - bpf_prog_query() enforces bpf_net_capable(), requiring CAP_NET_ADMIN or CAP_SYS_ADMIN; both are delegable and obtainable inside an unprivileged user namespace (unshare -Urn) on typical distributions, so this is Low rather than init-namespace administrator.\nUI:N - Exploitation requires only the attacker's own bpf(BPF_PROG_QUERY) syscall (or an auto-invoked legacy-sized query after kernel upgrade); no separate victim mount, file open, or interactive action is needed.\nS:U - copy_to_user() writes past the caller-supplied userspace buffer boundary, corrupting adjacent mappings in the calling process; it does not corrupt kernel heap/slab memory or cross VM, IOMMU, or container-to-host security boundaries.\nC:H - The kernel performs an out-of-bounds 8-byte write past the declared bpf_attr size; per CNA guidance any such memory corruption can be leveraged for information disclosure via adjacent userspace secrets, not merely a bounded metadata leak.\nI:H - The unconditional copy_to_user of query.revision at offset 56 when size is below offsetofend(revision) is an out-of-bounds write of up to 8 bytes (revision value partly influenced by prior cgroup BPF attach/detach), enabling userspace heap/stack corruption and potential code execution.\nA:H - The OOB write can crash or hang privileged BPF/cgroup management daemons (containerd, Cilium, kubelet) still issuing legacy-sized BPF_PROG_QUERY after a 6.17+ upgrade, and malicious CAP_NET_ADMIN callers can repeatedly corrupt adjacent mappings to induce process termination."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["include/linux/bpf-cgroup.h", "kernel/bpf/cgroup.c", "kernel/bpf/syscall.c"], "versions": [{"version": "195814a38a6a712bcb44d3dfa5109e926e92bec4", "lessThan": "b78eb6efbf052d44a3a14726aa7c7d5aa2e544d7", "status": "affected", "versionType": "git"}, {"version": "1209339844601ec1766f4ff430673fbcfe42bb51", "lessThan": "a7131340d0f95df9a541257dccab5d85e6bcdd2b", "status": "affected", "versionType": "git"}, {"version": "1209339844601ec1766f4ff430673fbcfe42bb51", "lessThan": "d3d630e8a7f3421bc2d204b87bdff35b4432a8e3", "status": "affected", "versionType": "git"}, {"version": "1209339844601ec1766f4ff430673fbcfe42bb51", "lessThan": "21c4b99b27f3f85b89256e81b3e997dec0a460d0", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["include/linux/bpf-cgroup.h", "kernel/bpf/cgroup.c", "kernel/bpf/syscall.c"], "versions": [{"version": "6.17", "status": "affected"}, {"version": "0", "lessThan": "6.17", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "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": "6.17", "versionEndExcluding": "6.18.40"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.17", "versionEndExcluding": "7.1.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.17", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/b78eb6efbf052d44a3a14726aa7c7d5aa2e544d7"}, {"url": "https://git.kernel.org/stable/c/a7131340d0f95df9a541257dccab5d85e6bcdd2b"}, {"url": "https://git.kernel.org/stable/c/d3d630e8a7f3421bc2d204b87bdff35b4432a8e3"}, {"url": "https://git.kernel.org/stable/c/21c4b99b27f3f85b89256e81b3e997dec0a460d0"}], "title": "bpf: fix BPF_PROG_QUERY OOB write and cgroup backward compat", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["include/linux/bpf-cgroup.h", "kernel/bpf/cgroup.c", "kernel/bpf/syscall.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "b78eb6efbf052d44a3a14726aa7c7d5aa2e544d7", "status": "affected", "version": "195814a38a6a712bcb44d3dfa5109e926e92bec4", "versionType": "git"}, {"lessThan": "a7131340d0f95df9a541257dccab5d85e6bcdd2b", "status": "affected", "version": "1209339844601ec1766f4ff430673fbcfe42bb51", "versionType": "git"}, {"lessThan": "d3d630e8a7f3421bc2d204b87bdff35b4432a8e3", "status": "affected", "version": "1209339844601ec1766f4ff430673fbcfe42bb51", "versionType": "git"}, {"lessThan": "21c4b99b27f3f85b89256e81b3e997dec0a460d0", "status": "affected", "version": "1209339844601ec1766f4ff430673fbcfe42bb51", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["include/linux/bpf-cgroup.h", "kernel/bpf/cgroup.c", "kernel/bpf/syscall.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.17"}, {"lessThan": "6.17", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.40", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.5", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: fix BPF_PROG_QUERY OOB write and cgroup backward compat\n\nBPF_PROG_QUERY writes back the 'query.revision' field unconditionally to\nuserspace. If userspace passes a smaller 'bpf_attr' structure (e.g. 40\nbytes, which was the layout before the addition of 'query.revision'),\nthe kernel performs an out-of-bounds write.\n\nFix this by propagating the user-provided attribute size 'uattr_size'\ndown to the cgroup query handlers, and conditionally skipping writing\nthe revision field to userspace when the provided buffer size is\ninsufficient.\n\nquery.revision in bpf_mprog_query is structurally identical to the\ncgroup case: a late tail field, written unconditionally.\n\nBut the backward-compat hazard is not the same.\n\nThe min-historical-size test is per command, and bpf_mprog_query only\nserves attach types that were born with revision in the struct:\n\n- tcx_prog_query -> BPF_TCX_INGRESS/EGRESS\n- netkit_prog_query -> BPF_NETKIT_PRIMARY/PEER\n\ntcx, netkit, the revision field, and bpf_mprog_query itself all landed in\nthe same v6.6 merge window (053c8e1f235d added the mprog query API +\nrevision; tcx in e420bed02507, netkit in 35dfaad7188c). There has never\nbeen a tcx/netkit BPF_PROG_QUERY userspace that doesn't know about\nrevision. So for these commands the minimum legitimate struct already\ncovers offset 56-64 \u2014 no old binary can be broken here.\n\nContrast with cgroup: BPF_PROG_QUERY on cgroup attach types shipped in\n2017; revision write-back was bolted on years later (120933984460). That\npath has a real population of pre-revision callers."}], "id": "CVE-2026-74371", "lastModified": "2026-09-14T12:17:45.663", "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"}]}, "published": "2026-08-15T06:22:38.857", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/21c4b99b27f3f85b89256e81b3e997dec0a460d0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a7131340d0f95df9a541257dccab5d85e6bcdd2b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b78eb6efbf052d44a3a14726aa7c7d5aa2e544d7"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d3d630e8a7f3421bc2d204b87bdff35b4432a8e3"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: bpf: fix BPF_PROG_QUERY OOB write and cgroup backward compat", "id": "2516902", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2516902"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-787", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nbpf: fix BPF_PROG_QUERY OOB write and cgroup backward compat\nBPF_PROG_QUERY writes back the 'query.revision' field unconditionally to\nuserspace. If userspace passes a smaller 'bpf_attr' structure (e.g. 40\nbytes, which was the layout before the addition of 'query.revision'),\nthe kernel performs an out-of-bounds write.\nFix this by propagating the user-provided attribute size 'uattr_size'\ndown to the cgroup query handlers, and conditionally skipping writing\nthe revision field to userspace when the provided buffer size is\ninsufficient.\nquery.revision in bpf_mprog_query is structurally identical to the\ncgroup case: a late tail field, written unconditionally.\nBut the backward-compat hazard is not the same.\nThe min-historical-size test is per command, and bpf_mprog_query only\nserves attach types that were born with revision in the struct:\n- tcx_prog_query -> BPF_TCX_INGRESS/EGRESS\n- netkit_prog_query -> BPF_NETKIT_PRIMARY/PEER\ntcx, netkit, the revision field, and bpf_mprog_query itself all landed in\nthe same v6.6 merge window (053c8e1f235d added the mprog query API +\nrevision; tcx in e420bed02507, netkit in 35dfaad7188c). There has never\nbeen a tcx/netkit BPF_PROG_QUERY userspace that doesn't know about\nrevision. So for these commands the minimum legitimate struct already\ncovers offset 56-64 \u2014 no old binary can be broken here.\nContrast with cgroup: BPF_PROG_QUERY on cgroup attach types shipped in\n2017; revision write-back was bolted on years later (120933984460). That\npath has a real population of pre-revision callers.", "A flaw was found in the Linux kernel's BPF_PROG_QUERY functionality. A local attacker could exploit this by providing a specially crafted `bpf_attr` structure with an insufficient size. This could lead to an out-of-bounds write, a memory corruption vulnerability where data is written beyond its allocated memory area, potentially causing system instability or other impacts."], "name": "CVE-2026-74371", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "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": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-08-15T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-74371\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-74371\nhttps://lore.kernel.org/linux-cve-announce/2026081503-CVE-2026-74371-aaa3@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1209339844601ec1766f4ff430673fbcfe42bb51,a7131340d0f95df9a541257dccab5d85e6bcdd2b)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1209339844601ec1766f4ff430673fbcfe42bb51,d3d630e8a7f3421bc2d204b87bdff35b4432a8e3)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1209339844601ec1766f4ff430673fbcfe42bb51,21c4b99b27f3f85b89256e81b3e997dec0a460d0)"}}], "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": "6.17"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,6.17)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.40,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.5,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-rc1,*]"}}], "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": "2026-08-15T13:30:04.658819+00:00", "updated": "2026-08-22T00:00:16.116559+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-120", "CWE-787"]}