{"id":"CVE-2026-23271","state":"PUBLISHED","title":"perf: Fix __perf_event_overflow() vs perf_remove_from_context() race","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf: Fix __perf_event_overflow() vs perf_remove_from_context() race\n\nMake sure that __perf_event_overflow() runs with IRQs disabled for all\npossible callchains. Specifically the software events can end up running\nit with only preemption disabled.\n\nThis opens up a race vs perf_event_exit_event() and friends that will go\nand free various things the overflow path expects to be present, like\nthe BPF program.","publishedAt":"2026-03-20T08:08:46.711Z","updatedAt":"2026-10-19T18:35:40.719Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"592903cdcbf606a838056bae6d03fc557806c914","status":"affected","lessThan":"4df1a45819e50993cb351682a6ae8e7ed2d233a0","versionType":"git"},{"version":"592903cdcbf606a838056bae6d03fc557806c914","status":"affected","lessThan":"4f8d5812337871227bb2c98669a87c306a2f86ef","versionType":"git"},{"version":"592903cdcbf606a838056bae6d03fc557806c914","status":"affected","lessThan":"5c48fdc4b4623533d86e279f51531a7ba212eb87","versionType":"git"},{"version":"592903cdcbf606a838056bae6d03fc557806c914","status":"affected","lessThan":"3f89b61dd504c5b6711de9759e053b082f9abf12","versionType":"git"},{"version":"592903cdcbf606a838056bae6d03fc557806c914","status":"affected","lessThan":"bb190628fe5f2a73ba762a9972ba16c5e895f73e","versionType":"git"},{"version":"592903cdcbf606a838056bae6d03fc557806c914","status":"affected","lessThan":"c9bc1753b3cc41d0e01fbca7f035258b5f4db0ae","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/events/core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.31","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.31","versionType":"semver"},{"version":"6.1.167","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.130","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.77","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.17","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.7","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/events/core.c"]}],"references":["https://git.kernel.org/stable/c/4df1a45819e50993cb351682a6ae8e7ed2d233a0","https://git.kernel.org/stable/c/4f8d5812337871227bb2c98669a87c306a2f86ef","https://git.kernel.org/stable/c/5c48fdc4b4623533d86e279f51531a7ba212eb87","https://git.kernel.org/stable/c/3f89b61dd504c5b6711de9759e053b082f9abf12","https://git.kernel.org/stable/c/bb190628fe5f2a73ba762a9972ba16c5e895f73e","https://git.kernel.org/stable/c/c9bc1753b3cc41d0e01fbca7f035258b5f4db0ae","https://cert-portal.siemens.com/productcert/html/ssa-082556.html","https://cert-portal.siemens.com/productcert/html/ssa-019113.html","https://cert-portal.siemens.com/productcert/html/ssa-457936.html","https://cert-portal.siemens.com/productcert/html/ssa-784472.html"],"weaknesses":["CWE-362"],"ingestedAt":"2026-10-29T20:11:21.040Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/23xxx/CVE-2026-23271.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-23271","state":"PUBLISHED","datePublished":"2026-03-20T08:08:46.711Z","dateUpdated":"2026-10-19T18:35:40.719Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-01-13T15:37:45.991Z"},"containers":{"cna":{"title":"perf: Fix __perf_event_overflow() vs perf_remove_from_context() race","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf: Fix __perf_event_overflow() vs perf_remove_from_context() race\n\nMake sure that __perf_event_overflow() runs with IRQs disabled for all\npossible callchains. 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There is no crossing of virtualization or sandbox boundaries.\nC:H - The use-after-free on the perf_event structure gives the attacker control over freed memory contents via heap spraying, enabling arbitrary kernel memory reads through controlled function pointer calls.\nI:H - The UAF includes a function pointer call (event->overflow_handler) from potentially attacker-controlled freed memory, providing a direct code execution primitive for arbitrary kernel code execution.\nA:H - The use-after-free will cause kernel crashes (oops/panic) even without sophisticated exploitation, as accessing freed memory leads to immediate instability."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:21:01.693Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.31","versionEndExcluding":"6.1.167"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.31","versionEndExcluding":"6.6.130"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.31","versionEndExcluding":"6.12.77"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.31","versionEndExcluding":"6.18.17"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.31","versionEndExcluding":"6.19.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.31","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.5","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.5","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.5","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.5","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - 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