{"id":"CVE-2026-98268","summary":"perf: Fix null pointer access in is_include_guest_event()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf: Fix null pointer access in is_include_guest_event()\n\nA typical module unload occurring event when there is an active perf\nconnection leads to freeing of the pmu pointer. The call log is something\nlike:\n ..\n __pmu_detach_event\n pmu_detach_event\n pmu_detach_events\n perf_pmu_unregister\n ..\n\n__pmu_detach_event() sets event-\u003epmu to null. When the perf connection\nfinally is closed, the following stack trace is observed:\n\n Oops: general protection fault, kernel NULL pointer dereference\n ...\n RIP: 0010:_free_event+0x3e/0x370\n ...\n Call Trace:\n ...\n perf_event_release_kernel+0x260/0x2d0\n perf_release+0x12/0x20\n\nA call to mediated_pmu_unaccount_event() inside _free_event() is the root\ncause of this crash. Adding a check inside is_include_guest_event() ensures\nwe don't accidentally access a null pmu ptr. In addition to this, we will\nnow call mediated_pmu_unaccount_event() before clearing the pmu ptr so that\nnr_include_guest_events counts are maintained correctly.","modified":"2026-10-07T02:47:30.243930714Z","published":"2026-10-06T08:45:30.917Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98268.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7fa9a465ae8f07c0e4685db6edb6a6f984dbd784"},{"type":"WEB","url":"https://git.kernel.org/stable/c/88aed0422f39b22406f35f1e758cea25e7bbcfb5"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98268.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98268"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"eff95e170275d9e80b968f335cd03d0ac250d2d1"},{"fixed":"7fa9a465ae8f07c0e4685db6edb6a6f984dbd784"},{"fixed":"88aed0422f39b22406f35f1e758cea25e7bbcfb5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98268.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.0.0"},{"fixed":"7.2.8"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98268.json"}}],"schema_version":"1.9.0"}