{"id":"CVE-2026-72237","summary":"perf/x86/amd/brs: Fix kernel address leakage","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf/x86/amd/brs: Fix kernel address leakage\n\nA user-only branch stack can contain branches that originate from\nthe kernel. As a result, kernel addresses are exposed to user space\neven when PERF_SAMPLE_BRANCH_USER is requested. On AMD processors\nsupporting X86_FEATURE_BRS (Zen 3 only), perf can still report entries\nsuch as SYSRET/interrupt returns for which the branch-from addresses\nare in the kernel.\n\nE.g.\n\n  $ perf record -j any,u -c 4000 -e branch-brs -o - -- \\\n        perf bench syscall basic --loop 1000 | \\\n        perf script -i - -F brstack|tr ' ' '\\n'| \\\n        grep -E '0x[89a-f][0-9a-f]{15}'\n\n  ...\n  0xffffffff810001c4/0x72e2e32955eb/-/-/-/0//-\n  0xffffffff810001c4/0x72e2d94a9821/-/-/-/0//-\n  0xffffffff810001c4/0x72e2d94ffa1b/-/-/-/0//-\n  ...\n\nBRS provides no hardware branch filtering, so privilege level\nfiltering is performed entirely in software. However, amd_brs_match_plm()\nonly validates the branch-to address against the requested privilege\nlevels. For branches from the kernel to user space, the branch-from\naddress is left unchecked and is leaked. Extend the software filter to\nalso validate the branch-from address, so that any branch record whose\nbranch-from address is in the kernel is dropped when\nPERF_SAMPLE_BRANCH_USER is requested.","modified":"2026-08-21T03:30:40.241104812Z","published":"2026-08-15T05:54:26.685Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72237.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/046f6244da9b68e463a849b21446b9424e531491"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2e706be56f418718bb3ae66c0aa94f9b61150e6d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/47915e855fb38b42133e31ba917d99565f862154"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4f949bc3913a6e3ce3b8574ac6ed1da8ec7a5ad1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/90843d00dbc61220b66408ea0d8775cae9e51f70"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ac44b4a3d6137489f8fa2e794b12e849c6b22eaa"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72237.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-72237"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"8910075d61a37e5b0d82e6c83ed9a0a31fe9ea08"},{"fixed":"4f949bc3913a6e3ce3b8574ac6ed1da8ec7a5ad1"},{"fixed":"ac44b4a3d6137489f8fa2e794b12e849c6b22eaa"},{"fixed":"90843d00dbc61220b66408ea0d8775cae9e51f70"},{"fixed":"046f6244da9b68e463a849b21446b9424e531491"},{"fixed":"2e706be56f418718bb3ae66c0aa94f9b61150e6d"},{"fixed":"47915e855fb38b42133e31ba917d99565f862154"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72237.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.19.0"},{"fixed":"6.1.183"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.97"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.40"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72237.json"}}],"schema_version":"1.9.0"}