{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-74637", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.922Z", "datePublished": "2026-08-22T15:32:16.755Z", "dateUpdated": "2026-08-22T15:32:16.755Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-22T15:32:16.755Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nperf/core: Fix group leader use-after-free after sibling detach\n\nperf_group_detach() handles leader and sibling detach differently. When the\ngroup leader is detached, all siblings are promoted to singleton events and\ntheir group_leader pointer is reset to themselves. When a sibling is\ndetached, it is removed from the leader's sibling_list, but its\ngroup_leader pointer is left pointing at the old leader.\n\nThat is harmless when the sibling is being closed and freed immediately, as\nin the DETACH_DEAD path. It is not safe when the sibling is detached but\nkept alive, such as during CPU hotplug with DETACH_GROUP. In that case the\nsibling is removed from the context, while its file descriptor can still\nkeep it alive.\n\nA typical failing sequence is:\n\n - A group contains leader L and sibling S.\n - CPU hot-unplug detaches S with DETACH_GROUP, removing it from\n L->sibling_list but leaving S->group_leader == L.\n - L is later closed and freed.\n - A PERF_IOC_FLAG_GROUP ioctl on S follows S->group_leader and\n dereferences the freed leader.\n\nThis was reproduced by running the perf event fuzzer, CPU hotplug, and a\nstress workload concurrently:\n\n Unable to handle kernel paging request at virtual address 006b6b6b6b6b6cdb\n CPU: 2 PID: 12489 Comm: perf_fuzzer 6.18.7 PREEMPT\n pc : perf_ioctl+0x34c/0xc68\n x20: ffffff89a3fa2c70 x8 : 6b6b6b6b6b6b6b6b\n Code: 943c4a0e 340047a0 f9404a94 f9411e88 (f940b908)\n Call trace:\n perf_ioctl+0x34c/0xc68 (P)\n __arm64_sys_ioctl+0xa0/0xf4\n invoke_syscall+0x58/0xe4\n el0_svc_common+0xa8/0xdc\n do_el0_svc+0x1c/0x28\n el0_svc+0x40/0xc0\n el0t_64_sync_handler+0x68/0xdc\n el0t_64_sync+0x1c4/0x1c8\n\nThe fault happened in perf_ioctl(), where perf_event_for_each() follows\nthe stale group_leader pointer and perf_event_for_each_child() then\ndereferences the freed leader's context.\n\nFix the use-after-free by promoting the detached sibling to a singleton.\nAlso fix __event_disable() cgroup accounting and event state change."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/events/core.c"], "versions": [{"version": "8a49542c0554af7d0073aac0ee73ee65b807ef34", "lessThan": "a979a642402d0b1f856c7a729b4cb2d92de4cf2f", "status": "affected", "versionType": "git"}, {"version": "8a49542c0554af7d0073aac0ee73ee65b807ef34", "lessThan": "1e7abfeb23c12bf46f6457e4a3e1a1a300d50619", "status": "affected", "versionType": "git"}, {"version": "8a49542c0554af7d0073aac0ee73ee65b807ef34", "lessThan": "42c5ca1f0a288a52878bd72a5595b08261057438", "status": "affected", "versionType": "git"}, {"version": "e732ebc42aea321ee84514330eb3a675307fcc83", "status": "affected", "versionType": "git"}, {"version": "2.6.34.14", "lessThan": "2.6.35", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/events/core.c"], "versions": [{"version": "2.6.35", "status": "affected"}, {"version": "0", "lessThan": "2.6.35", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.45", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.9", "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": "2.6.35", "versionEndExcluding": "6.18.45"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.35", "versionEndExcluding": "7.1.9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.35", "versionEndExcluding": "7.2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34.14"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/a979a642402d0b1f856c7a729b4cb2d92de4cf2f"}, {"url": "https://git.kernel.org/stable/c/1e7abfeb23c12bf46f6457e4a3e1a1a300d50619"}, {"url": "https://git.kernel.org/stable/c/42c5ca1f0a288a52878bd72a5595b08261057438"}], "title": "perf/core: Fix group leader use-after-free after sibling detach", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/events/core.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "a979a642402d0b1f856c7a729b4cb2d92de4cf2f", "status": "affected", "version": "8a49542c0554af7d0073aac0ee73ee65b807ef34", "versionType": "git"}, {"lessThan": "1e7abfeb23c12bf46f6457e4a3e1a1a300d50619", "status": "affected", "version": "8a49542c0554af7d0073aac0ee73ee65b807ef34", "versionType": "git"}, {"lessThan": "42c5ca1f0a288a52878bd72a5595b08261057438", "status": "affected", "version": "8a49542c0554af7d0073aac0ee73ee65b807ef34", "versionType": "git"}, {"status": "affected", "version": "e732ebc42aea321ee84514330eb3a675307fcc83", "versionType": "git"}, {"lessThan": "2.6.35", "status": "affected", "version": "2.6.34.14", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/events/core.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "2.6.35"}, {"lessThan": "2.6.35", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.45", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.9", "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\nperf/core: Fix group leader use-after-free after sibling detach\n\nperf_group_detach() handles leader and sibling detach differently. When the\ngroup leader is detached, all siblings are promoted to singleton events and\ntheir group_leader pointer is reset to themselves. When a sibling is\ndetached, it is removed from the leader's sibling_list, but its\ngroup_leader pointer is left pointing at the old leader.\n\nThat is harmless when the sibling is being closed and freed immediately, as\nin the DETACH_DEAD path. It is not safe when the sibling is detached but\nkept alive, such as during CPU hotplug with DETACH_GROUP. In that case the\nsibling is removed from the context, while its file descriptor can still\nkeep it alive.\n\nA typical failing sequence is:\n\n - A group contains leader L and sibling S.\n - CPU hot-unplug detaches S with DETACH_GROUP, removing it from\n L->sibling_list but leaving S->group_leader == L.\n - L is later closed and freed.\n - A PERF_IOC_FLAG_GROUP ioctl on S follows S->group_leader and\n dereferences the freed leader.\n\nThis was reproduced by running the perf event fuzzer, CPU hotplug, and a\nstress workload concurrently:\n\n Unable to handle kernel paging request at virtual address 006b6b6b6b6b6cdb\n CPU: 2 PID: 12489 Comm: perf_fuzzer 6.18.7 PREEMPT\n pc : perf_ioctl+0x34c/0xc68\n x20: ffffff89a3fa2c70 x8 : 6b6b6b6b6b6b6b6b\n Code: 943c4a0e 340047a0 f9404a94 f9411e88 (f940b908)\n Call trace:\n perf_ioctl+0x34c/0xc68 (P)\n __arm64_sys_ioctl+0xa0/0xf4\n invoke_syscall+0x58/0xe4\n el0_svc_common+0xa8/0xdc\n do_el0_svc+0x1c/0x28\n el0_svc+0x40/0xc0\n el0t_64_sync_handler+0x68/0xdc\n el0t_64_sync+0x1c4/0x1c8\n\nThe fault happened in perf_ioctl(), where perf_event_for_each() follows\nthe stale group_leader pointer and perf_event_for_each_child() then\ndereferences the freed leader's context.\n\nFix the use-after-free by promoting the detached sibling to a singleton.\nAlso fix __event_disable() cgroup accounting and event state change."}], "id": "CVE-2026-74637", "lastModified": "2026-08-22T16:16:36.890", "metrics": {}, "published": "2026-08-22T16:16:36.890", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/1e7abfeb23c12bf46f6457e4a3e1a1a300d50619"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/42c5ca1f0a288a52878bd72a5595b08261057438"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a979a642402d0b1f856c7a729b4cb2d92de4cf2f"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[8a49542c0554af7d0073aac0ee73ee65b807ef34,a979a642402d0b1f856c7a729b4cb2d92de4cf2f)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[8a49542c0554af7d0073aac0ee73ee65b807ef34,1e7abfeb23c12bf46f6457e4a3e1a1a300d50619)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[8a49542c0554af7d0073aac0ee73ee65b807ef34,42c5ca1f0a288a52878bd72a5595b08261057438)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "e732ebc42aea321ee84514330eb3a675307fcc83"}}, {"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[2.6.34.14,2.6.35)"}}], "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": "2.6.35"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,2.6.35)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.18.45,6.18.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.1.9,7.1.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2,*]"}}], "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": "2026-08-22T19:15:03.628177+00:00", "updated": "2026-08-22T19:45:03.038471+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-416"]}