CVE-2026-72042

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-72042", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-09T03:40:39.902Z", "datePublished": "2026-08-15T05:52:01.454Z", "dateUpdated": "2026-08-17T05:39:41.572Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:39:41.572Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipmi: Fix user refcount underflow in event delivery\n\nipmi_alloc_recv_msg(user) takes the temporary user reference owned by the\nreceive message, and ipmi_free_recv_msg() drops it again. If event delivery\nfails after allocating receive messages for earlier users,\nhandle_read_event_rsp() rolls those messages back with\nipmi_free_recv_msg().\n\nThat rollback path still drops user->refcount explicitly after freeing each\nmessage. The extra put can free a user that remains linked on intf->users,\nso later event delivery may dereference a freed user or trip refcount_t's\naddition-on-zero warning when ipmi_alloc_recv_msg() tries to acquire\nanother reference.\n\nRemove the stale explicit put and the now-dead user assignment. Keep the\nlist_del() and ipmi_free_recv_msg() calls; they are the required rollback\noperations."}], "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 - Exploitation requires local setup via /dev/ipmiN (open, IPMICTL_SET_GETS_EVENTS, message flooding); the refcount bug is in handle_read_event_rsp() during host-side BMC event processing, not via a remote packet path to the kernel.\nAC:L - An attacker with IPMI device access controls both sides: multiple fds, gets_events registration, filling one user's outstanding-message limit to force EBUSY, and generating/waiting for BMC events via their own IPMI commands.\nPR:L - ipmi_open/ipmi_create_user perform no capability() check; access is gated only by /dev/ipmiN DAC, and BMC-equipped servers often grant that node to a non-root management group (ipmi) for ipmitool/freeipmi.\nUI:N - No victim interaction is required; the attacker drives all setup and triggering through their own IPMI file descriptors and ioctls.\nS:U - This is a host-kernel heap use-after-free of struct ipmi_user within the same OS security authority, with no VM escape, IOMMU bypass, or sandbox boundary crossing.\nC:H - Premature free_ipmi_user() leaves a dangling ipmi_user on intf->users; later iterations call kref_get and read handler pointers from freed slab memory, yielding arbitrary kernel read primitives per UAF guidance.\nI:H - Freed ipmi_user objects contain function pointers (handler->ipmi_recv_hndl); smi_work later invokes these on reclaimed memory, enabling heap spray and control-flow hijack for arbitrary kernel write/code execution.\nA:H - The extra kref_put causes refcount underflow warnings and use-after-free of ipmi_user; subsequent event delivery dereferences freed memory and readily triggers kernel oops/panic under KASAN/poisoning."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/char/ipmi/ipmi_msghandler.c"], "versions": [{"version": "b52da4054ee0bf9ecb44996f2c83236ff50b3812", "lessThan": "ddbb6e3dc9bb4743de686aa1598c31e745cee76b", "status": "affected", "versionType": "git"}, {"version": "b52da4054ee0bf9ecb44996f2c83236ff50b3812", "lessThan": "7be349d4fcc5e065295b83418a22d27a68afbdb6", "status": "affected", "versionType": "git"}, {"version": "b52da4054ee0bf9ecb44996f2c83236ff50b3812", "lessThan": "6aa9e61c46465d231e9beddf56af7effd71be682", "status": "affected", "versionType": "git"}, {"version": "f63723ca7d7623f9dae1990973cd158671f03c56", "status": "affected", "versionType": "git"}, {"version": "348121b29594d42d1635648fd3ed31dfa25351d5", "status": "affected", "versionType": "git"}, {"version": "53d6e403affbf6df2c859a0ea00ccfc1e72090ca", "status": "affected", "versionType": "git"}, {"version": "0ed73be9a2547ffb9b5c1d879ad9bfab73d920b5", "status": "affected", "versionType": "git"}, {"version": "6.1.157", "lessThan": "6.2", "status": "affected", "versionType": "semver"}, {"version": "6.6.113", "lessThan": "6.7", "status": "affected", "versionType": "semver"}, {"version": "6.12.54", "lessThan": "6.13", "status": "affected", "versionType": "semver"}, {"version": "6.17.4", "lessThan": "6.18", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/char/ipmi/ipmi_msghandler.c"], "versions": [{"version": "6.18", "status": "affected"}, {"version": "0", "lessThan": "6.18", "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": "6.18", "versionEndExcluding": "6.18.40"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18", "versionEndExcluding": "7.1.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18", "versionEndExcluding": "7.2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.157"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.113"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12.54"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.17.4"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/ddbb6e3dc9bb4743de686aa1598c31e745cee76b"}, {"url": "https://git.kernel.org/stable/c/7be349d4fcc5e065295b83418a22d27a68afbdb6"}, {"url": "https://git.kernel.org/stable/c/6aa9e61c46465d231e9beddf56af7effd71be682"}], "title": "ipmi: Fix user refcount underflow in event delivery", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/char/ipmi/ipmi_msghandler.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "ddbb6e3dc9bb4743de686aa1598c31e745cee76b", "status": "affected", "version": "b52da4054ee0bf9ecb44996f2c83236ff50b3812", "versionType": "git"}, {"lessThan": "7be349d4fcc5e065295b83418a22d27a68afbdb6", "status": "affected", "version": "b52da4054ee0bf9ecb44996f2c83236ff50b3812", "versionType": "git"}, {"lessThan": "6aa9e61c46465d231e9beddf56af7effd71be682", "status": "affected", "version": "b52da4054ee0bf9ecb44996f2c83236ff50b3812", "versionType": "git"}, {"status": "affected", "version": "f63723ca7d7623f9dae1990973cd158671f03c56", "versionType": "git"}, {"status": "affected", "version": "348121b29594d42d1635648fd3ed31dfa25351d5", "versionType": "git"}, {"status": "affected", "version": "53d6e403affbf6df2c859a0ea00ccfc1e72090ca", "versionType": "git"}, {"status": "affected", "version": "0ed73be9a2547ffb9b5c1d879ad9bfab73d920b5", "versionType": "git"}, {"lessThan": "6.2", "status": "affected", "version": "6.1.157", "versionType": "semver"}, {"lessThan": "6.7", "status": "affected", "version": "6.6.113", "versionType": "semver"}, {"lessThan": "6.13", "status": "affected", "version": "6.12.54", "versionType": "semver"}, {"lessThan": "6.18", "status": "affected", "version": "6.17.4", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/char/ipmi/ipmi_msghandler.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.18"}, {"lessThan": "6.18", "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\nipmi: Fix user refcount underflow in event delivery\n\nipmi_alloc_recv_msg(user) takes the temporary user reference owned by the\nreceive message, and ipmi_free_recv_msg() drops it again. If event delivery\nfails after allocating receive messages for earlier users,\nhandle_read_event_rsp() rolls those messages back with\nipmi_free_recv_msg().\n\nThat rollback path still drops user->refcount explicitly after freeing each\nmessage. The extra put can free a user that remains linked on intf->users,\nso later event delivery may dereference a freed user or trip refcount_t's\naddition-on-zero warning when ipmi_alloc_recv_msg() tries to acquire\nanother reference.\n\nRemove the stale explicit put and the now-dead user assignment. Keep the\nlist_del() and ipmi_free_recv_msg() calls; they are the required rollback\noperations."}], "id": "CVE-2026-72042", "lastModified": "2026-08-17T06:18:02.133", "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": "2026-08-15T06:21:13.370", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/6aa9e61c46465d231e9beddf56af7effd71be682"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7be349d4fcc5e065295b83418a22d27a68afbdb6"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/ddbb6e3dc9bb4743de686aa1598c31e745cee76b"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: ipmi: Fix user refcount underflow in event delivery", "id": "2516235", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2516235"}, "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-825", "details": ["A flaw was found in the Linux kernel's Intelligent Platform Management Interface (IPMI) subsystem. An issue in the event delivery mechanism, specifically a reference count underflow, can lead to a use-after-free vulnerability. This occurs when a user's reference count is prematurely decremented during event delivery rollback, allowing for the potential dereferencing of freed memory. This could result in system instability or a denial of service."], "name": "CVE-2026-72042", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not 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": "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-2026-72042\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-72042\nhttps://lore.kernel.org/linux-cve-announce/2026081513-CVE-2026-72042-3b9c@gregkh/T"], "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[b52da4054ee0bf9ecb44996f2c83236ff50b3812,ddbb6e3dc9bb4743de686aa1598c31e745cee76b)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[b52da4054ee0bf9ecb44996f2c83236ff50b3812,7be349d4fcc5e065295b83418a22d27a68afbdb6)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[b52da4054ee0bf9ecb44996f2c83236ff50b3812,6aa9e61c46465d231e9beddf56af7effd71be682)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f63723ca7d7623f9dae1990973cd158671f03c56,*]"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[348121b29594d42d1635648fd3ed31dfa25351d5,*]"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[53d6e403affbf6df2c859a0ea00ccfc1e72090ca,*]"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0ed73be9a2547ffb9b5c1d879ad9bfab73d920b5,*]"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.1.157,6.2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.6.113,6.7)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.12.54,6.13)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.17.4,6.18)"}}], "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": "generic", "value": "6.18"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.18)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.18.40,6.18.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.1.5,7.1.*]"}}, {"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": "2026-08-15T09:45:03.366127+00:00", "updated": "2026-08-17T21:00:14.150736+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}