{"cve":"CVE-2026-80602","nvd":{"published":"2026-08-28T08:16:44.070","modified":"2026-10-30T13:20:07.733","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf/x86/amd/lbr: 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_AMD_LBR_V2, perf can still report SYSRET/ERET\nentries for which the branch-from addresses are in the kernel.\n\nE.g.\n\n  $ perf record -e cycles -o - -j any,save_type,u -- \\\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  0xffffffff81001268/0x717a90a38f1a/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH\n  0xffffffff81001268/0x717a90a39157/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH\n  0xffffffff81001268/0x717a90a2c628/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH\n  0xffffffff81001268/0x717a90a41b60/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH\n  0xffffffff81001268/0x717a90a260db/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH\n  0xffffffff81001268/0x717a90a260db/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH\n  0xffffffff81001268/0x717a8bef1c30/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH\n  0xffffffff81001268/0x717a8e4d3c90/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH\n  ...\n\nThe reason is that the hardware filter only considers the privilege\nlevel applicable to the branch target. Extend software filtering to\nalso validate the branch-from addresses against br_sel, so that any\nbranch record whose branch-from address is in the kernel is dropped\nwhen PERF_SAMPLE_BRANCH_USER is requested.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/208ecca408b1707ad86ea247d3d3e09d3606fc13","https://git.kernel.org/stable/c/2a892294b83f541115c94b0bb637f39bef187657","https://git.kernel.org/stable/c/5ab0eba9c8819506bcb72348fd701f8a9006f95e","https://git.kernel.org/stable/c/5adfec05e804ce4bd3368b75df5e5b7b40ee960b","https://git.kernel.org/stable/c/5be478c1e08981ca91b34de310d7e2638171d9d8"],"products":[],"source":"nvd","synced_at":"2026-10-30T13:47:47.119061695+00:00"},"epss":{"cve":"CVE-2026-80602","score":0.00209,"percentile":0.11104,"date":"2026-10-30"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}