{"id":"CVE-2026-53370","state":"PUBLISHED","title":"perf/x86/intel: Improve validation and configuration of ACR masks","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf/x86/intel: Improve validation and configuration of ACR masks\n\nCurrently there are several issues on the user space ACR mask validation\nand configuration.\n- The validation for user space ACR mask (attr.config2) is incomplete,\n  e.g., the ACR mask could include the index which belongs to another\n  ACR events group, but it's not validated.\n- An early return on an invalid ACR mask caused all subsequent ACR groups\n  to be skipped.\n- The stale hardware ACR mask (hw.config1) is not cleared before setting\n  new hardware ACR mask.\n\nThe following changes address all of the above issues.\n- Figure out the event index group of an ACR group. Any bits in the\n  user-space mask not present in the index group are now dropped.\n- Instead of an early return on invalid bits, drop only the invalid\n  portions and continue iterating through all ACR events to ensure full\n  configuration.\n- Explicitly clear the stale hardware ACR mask for each event prior to\n  writing the new configuration.\n\nBesides, a non-leader event member of ACR group could be disabled in\ntheory. This could cause bit-shifting errors in the acr_mask of remaining\ngroup members. But since ACR sampling requires all events to be active,\nthis should not be a big concern in real use case. Add a \"FIXME\" comment\nto notice this risk.","publishedAt":"2026-07-19T09:10:30.990Z","updatedAt":"2026-07-19T09:10:30.990Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ec980e4facef8110f6fce27e5b6344660117f01f","status":"affected","lessThan":"aab56b95bee3ff79176b13443cd9d7cfe9747df0","versionType":"git"},{"version":"ec980e4facef8110f6fce27e5b6344660117f01f","status":"affected","lessThan":"c05e01cef47d9b4969eae2dcf9467e2a555bcb4f","versionType":"git"},{"version":"ec980e4facef8110f6fce27e5b6344660117f01f","status":"affected","lessThan":"5ad732a56be46aabf158c16aa0c095291727aaef","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/events/intel/core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.16","versionType":"semver"},{"version":"6.18.30","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.7","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/events/intel/core.c"]}],"references":["https://git.kernel.org/stable/c/aab56b95bee3ff79176b13443cd9d7cfe9747df0","https://git.kernel.org/stable/c/c05e01cef47d9b4969eae2dcf9467e2a555bcb4f","https://git.kernel.org/stable/c/5ad732a56be46aabf158c16aa0c095291727aaef"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/53xxx/CVE-2026-53370.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-53370","state":"PUBLISHED","datePublished":"2026-07-19T09:10:30.990Z","dateUpdated":"2026-07-19T09:10:30.990Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-06-09T07:44:35.401Z"},"containers":{"cna":{"title":"perf/x86/intel: Improve validation and configuration of ACR masks","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf/x86/intel: Improve validation and configuration of ACR masks\n\nCurrently there are several issues on the user space ACR mask validation\nand configuration.\n- The validation for user space ACR mask (attr.config2) is incomplete,\n  e.g., the ACR mask could include the index which belongs to another\n  ACR events group, but it's not validated.\n- An early return on an invalid ACR mask caused all subsequent ACR groups\n  to be skipped.\n- The stale hardware ACR mask (hw.config1) is not cleared before setting\n  new hardware ACR mask.\n\nThe following changes address all of the above issues.\n- Figure out the event index group of an ACR group. Any bits in the\n  user-space mask not present in the index group are now dropped.\n- Instead of an early return on invalid bits, drop only the invalid\n  portions and continue iterating through all ACR events to ensure full\n  configuration.\n- Explicitly clear the stale hardware ACR mask for each event prior to\n  writing the new configuration.\n\nBesides, a non-leader event member of ACR group could be disabled in\ntheory. This could cause bit-shifting errors in the acr_mask of remaining\ngroup members. But since ACR sampling requires all events to be active,\nthis should not be a big concern in real use case. Add a \"FIXME\" comment\nto notice this risk."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ec980e4facef8110f6fce27e5b6344660117f01f","status":"affected","lessThan":"aab56b95bee3ff79176b13443cd9d7cfe9747df0","versionType":"git"},{"version":"ec980e4facef8110f6fce27e5b6344660117f01f","status":"affected","lessThan":"c05e01cef47d9b4969eae2dcf9467e2a555bcb4f","versionType":"git"},{"version":"ec980e4facef8110f6fce27e5b6344660117f01f","status":"affected","lessThan":"5ad732a56be46aabf158c16aa0c095291727aaef","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/events/intel/core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.16","versionType":"semver"},{"version":"6.18.30","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.7","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/events/intel/core.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/aab56b95bee3ff79176b13443cd9d7cfe9747df0"},{"url":"https://git.kernel.org/stable/c/c05e01cef47d9b4969eae2dcf9467e2a555bcb4f"},{"url":"https://git.kernel.org/stable/c/5ad732a56be46aabf158c16aa0c095291727aaef"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-07-19T09:10:30.990Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"6.18.30"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"7.0.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"7.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}