{"id":"CVE-2026-97443","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf/ftrace: Fix WARNING in __unregister_ftrace_function\n\nperf_ftrace_function_unregister() unconditionally calls\nunregister_ftrace_function() without checking whether …","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf/ftrace: Fix WARNING in __unregister_ftrace_function\n\nperf_ftrace_function_unregister() unconditionally calls\nunregister_ftrace_function() without checking whether …","severity":"medium","vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < df097713b56ffac5eed32a9be2e7d27ac48d9087","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 7f845820afaad339341c2ae42bc7fdec175df9ea","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 9581123304b23049437324038698af9fb56ee663","Linux < 6.12.111","Linux < 6.18.53","Linux (all versions)"],"published":"2026-09-24","updated":"2026-09-25","sourceUpdated":"2026-09-25T13:17:28.023","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-97443","references":[{"url":"https://git.kernel.org/stable/c/7f845820afaad339341c2ae42bc7fdec175df9ea","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9581123304b23049437324038698af9fb56ee663","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/df097713b56ffac5eed32a9be2e7d27ac48d9087","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97443.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-97443"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2540498"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-97443"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97443"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-97443.mbox"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"ingestedAt":"2026-09-24T16:47:15.877Z","epss":0.00166,"epssPercentile":0.05794,"cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":["CWE-617"],"slug":"CVE-2026-97443","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nperf/ftrace: Fix WARNING in __unregister_ftrace_function\n\nperf_ftrace_function_unregister() unconditionally calls\nunregister_ftrace_function() without checking whether the ftrace_ops\nwas ever successfully registered. This triggers a WARN_ON in\n__unregister_ftrace_function() when the ops doesn't have\nFTRACE_OPS_FL_ENABLED set.\n\nThis can happen during perf_event_alloc() error cleanup when\nperf_trace_destroy() is called via __free_event() on an event whose\nftrace_ops registration failed or was already torn down by\nperf_try_init_event()'s err_destroy path.\n\nThe call path is:\n  perf_event_alloc() error cleanup\n    -> __free_event()\n      -> event->destroy() [tp_perf_event_destroy]\n        -> perf_trace_destroy()\n          -> perf_trace_event_close()\n            -> TRACE_REG_PERF_CLOSE\n              -> perf_ftrace_function_unregister()\n                -> unregister_ftrace_function()\n                  -> __unregister_ftrace_function()\n                    -> WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))\n\nFix this by checking FTRACE_OPS_FL_ENABLED before attempting to\nunregister. If the ops is not enabled, just free the filter and\nreturn success.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10 · no fix planned: Red Hat Enterprise Linux 10 · updated 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97443.json)","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":213548,"id":"CVE-2026-97443","ts":1790754772506,"field":"cvss","old":null,"new":"5.5"},{"seq":213547,"id":"CVE-2026-97443","ts":1790754772506,"field":"severity","old":"none","new":"medium"}]}