{"api_version":"1","generated_at":"2026-09-12T02:59:53+00:00","cve":"CVE-2026-89750","urls":{"html":"https://cve.report/CVE-2026-89750","api":"https://cve.report/api/cve/CVE-2026-89750.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-89750","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-89750"},"summary":{"title":"tracing/user_events: Clear copied tracing state before fork duplication","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing/user_events: Clear copied tracing state before fork duplication\n\ndup_task_struct() copies user_event_mm from the parent into the child,\nwithout grabbing a reference to it. user_event_mm_dup() should\nreplace it, but it leaves that copied pointer unmodified if\nuser_event_mm_alloc() fails.\n\nWhen the child exits, user_event_mm_remove() decrements a reference\nthe child never owned, which ultimately frees user_event_mm, while\nthe parent still as a stale pointer to it. This creates a UAF, which\nKASAN reports as:\n\n    BUG: KASAN: slab-use-after-free in\n    current_user_event_mm+0x51/0x1d0 Write of size 4 at addr\n    ffff888005010d30 by task init/44\n\n    Call Trace:\n     <TASK>\n     kasan_report+0xce/0x100\n     kasan_check_range+0x10f/0x1e0\n     current_user_event_mm+0x51/0x1d0\n     user_events_ioctl+0x82e/0x15c0\n     __x64_sys_ioctl+0x139/0x1c0\n     do_syscall_64+0xce/0x450\n     entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\n    Allocated by task 44:\n     __kasan_kmalloc+0x8f/0xa0\n     __kmalloc_cache_noprof+0x180/0x3a0\n     user_event_mm_alloc+0x3c/0x1f0\n     current_user_event_mm+0x88/0x1d0\n\n    Freed by task 42:\n     __kasan_slab_free+0x43/0x70\n     kfree+0x13a/0x390\n     process_one_work+0x696/0xf90\n     worker_thread+0x420/0xba0\n\nThe fix simply clears the copied pointer before any possible failure.\nIn case of failure, the child then has nothing to free.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-11 20:20:05","updated_at":"2026-09-11 20:20:05"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/63b39e49a4c9d68e010e96b26fc7374f0864f2b1","name":"https://git.kernel.org/stable/c/63b39e49a4c9d68e010e96b26fc7374f0864f2b1","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/25a0758cf6bdbfddac2be71124c9bd0692f4b0b1","name":"https://git.kernel.org/stable/c/25a0758cf6bdbfddac2be71124c9bd0692f4b0b1","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b799f67119aff179719a0b1e12441ebbdaaf62f9","name":"https://git.kernel.org/stable/c/b799f67119aff179719a0b1e12441ebbdaaf62f9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/390f6bd8583d177029d9df4bea6667509e55a765","name":"https://git.kernel.org/stable/c/390f6bd8583d177029d9df4bea6667509e55a765","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89750","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89750","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7235759084a4f8524a46bd2638885ff3b34ce279 63b39e49a4c9d68e010e96b26fc7374f0864f2b1 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7235759084a4f8524a46bd2638885ff3b34ce279 25a0758cf6bdbfddac2be71124c9bd0692f4b0b1 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7235759084a4f8524a46bd2638885ff3b34ce279 b799f67119aff179719a0b1e12441ebbdaaf62f9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7235759084a4f8524a46bd2638885ff3b34ce279 390f6bd8583d177029d9df4bea6667509e55a765 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.4","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.4 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.109 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.50 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.4 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["kernel/trace/trace_events_user.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"63b39e49a4c9d68e010e96b26fc7374f0864f2b1","status":"affected","version":"7235759084a4f8524a46bd2638885ff3b34ce279","versionType":"git"},{"lessThan":"25a0758cf6bdbfddac2be71124c9bd0692f4b0b1","status":"affected","version":"7235759084a4f8524a46bd2638885ff3b34ce279","versionType":"git"},{"lessThan":"b799f67119aff179719a0b1e12441ebbdaaf62f9","status":"affected","version":"7235759084a4f8524a46bd2638885ff3b34ce279","versionType":"git"},{"lessThan":"390f6bd8583d177029d9df4bea6667509e55a765","status":"affected","version":"7235759084a4f8524a46bd2638885ff3b34ce279","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["kernel/trace/trace_events_user.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.4"},{"lessThan":"6.4","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.109","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.50","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.4","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.109","versionStartIncluding":"6.4","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.50","versionStartIncluding":"6.4","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.4","versionStartIncluding":"6.4","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"6.4","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing/user_events: Clear copied tracing state before fork duplication\n\ndup_task_struct() copies user_event_mm from the parent into the child,\nwithout grabbing a reference to it. user_event_mm_dup() should\nreplace it, but it leaves that copied pointer unmodified if\nuser_event_mm_alloc() fails.\n\nWhen the child exits, user_event_mm_remove() decrements a reference\nthe child never owned, which ultimately frees user_event_mm, while\nthe parent still as a stale pointer to it. This creates a UAF, which\nKASAN reports as:\n\n    BUG: KASAN: slab-use-after-free in\n    current_user_event_mm+0x51/0x1d0 Write of size 4 at addr\n    ffff888005010d30 by task init/44\n\n    Call Trace:\n     <TASK>\n     kasan_report+0xce/0x100\n     kasan_check_range+0x10f/0x1e0\n     current_user_event_mm+0x51/0x1d0\n     user_events_ioctl+0x82e/0x15c0\n     __x64_sys_ioctl+0x139/0x1c0\n     do_syscall_64+0xce/0x450\n     entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\n    Allocated by task 44:\n     __kasan_kmalloc+0x8f/0xa0\n     __kmalloc_cache_noprof+0x180/0x3a0\n     user_event_mm_alloc+0x3c/0x1f0\n     current_user_event_mm+0x88/0x1d0\n\n    Freed by task 42:\n     __kasan_slab_free+0x43/0x70\n     kfree+0x13a/0x390\n     process_one_work+0x696/0xf90\n     worker_thread+0x420/0xba0\n\nThe fix simply clears the copied pointer before any possible failure.\nIn case of failure, the child then has nothing to free."}],"providerMetadata":{"dateUpdated":"2026-09-11T19:46:54.565Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/63b39e49a4c9d68e010e96b26fc7374f0864f2b1"},{"url":"https://git.kernel.org/stable/c/25a0758cf6bdbfddac2be71124c9bd0692f4b0b1"},{"url":"https://git.kernel.org/stable/c/b799f67119aff179719a0b1e12441ebbdaaf62f9"},{"url":"https://git.kernel.org/stable/c/390f6bd8583d177029d9df4bea6667509e55a765"}],"title":"tracing/user_events: Clear copied tracing state before fork duplication","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-89750","datePublished":"2026-09-11T19:46:54.565Z","dateReserved":"2026-09-11T19:38:34.762Z","dateUpdated":"2026-09-11T19:46:54.565Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-11 20:20:05","lastModifiedDate":"2026-09-11 20:20:05","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"89750","Ordinal":"1","Title":"tracing/user_events: Clear copied tracing state before fork dupl","CVE":"CVE-2026-89750","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"89750","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing/user_events: Clear copied tracing state before fork duplication\n\ndup_task_struct() copies user_event_mm from the parent into the child,\nwithout grabbing a reference to it. user_event_mm_dup() should\nreplace it, but it leaves that copied pointer unmodified if\nuser_event_mm_alloc() fails.\n\nWhen the child exits, user_event_mm_remove() decrements a reference\nthe child never owned, which ultimately frees user_event_mm, while\nthe parent still as a stale pointer to it. This creates a UAF, which\nKASAN reports as:\n\n    BUG: KASAN: slab-use-after-free in\n    current_user_event_mm+0x51/0x1d0 Write of size 4 at addr\n    ffff888005010d30 by task init/44\n\n    Call Trace:\n     <TASK>\n     kasan_report+0xce/0x100\n     kasan_check_range+0x10f/0x1e0\n     current_user_event_mm+0x51/0x1d0\n     user_events_ioctl+0x82e/0x15c0\n     __x64_sys_ioctl+0x139/0x1c0\n     do_syscall_64+0xce/0x450\n     entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\n    Allocated by task 44:\n     __kasan_kmalloc+0x8f/0xa0\n     __kmalloc_cache_noprof+0x180/0x3a0\n     user_event_mm_alloc+0x3c/0x1f0\n     current_user_event_mm+0x88/0x1d0\n\n    Freed by task 42:\n     __kasan_slab_free+0x43/0x70\n     kfree+0x13a/0x390\n     process_one_work+0x696/0xf90\n     worker_thread+0x420/0xba0\n\nThe fix simply clears the copied pointer before any possible failure.\nIn case of failure, the child then has nothing to free.","Type":"Description","Title":"tracing/user_events: Clear copied tracing state before fork dupl"}]}}}