{"apiVersion":"1.0","identifier":"CVE-2026-80602","description":"In the Linux kernel, the following vulnerability has been resolved: perf/x86/amd/lbr: Fix kernel address leakage A user-only branch stack can contain branches that originate from the kernel. As a result, kernel addresses are exposed to user space even when PERF_SAMPLE_BRANCH_USER is requested. On AMD processors supporting X86_FEATURE_AMD_LBR_V2, perf can still report SYSRET/ERET entries for which the branch-from addresses are in the kernel. E.g. $ perf record -e cycles -o - -j any,save_type,u -- \\ perf bench syscall basic --loop 1000 | \\ perf script -i - -F brstack|tr - - -\\n-| \\ grep -E -0x[89a-f][0-9a-f]{15}- ... 0xffffffff81001268/0x717a90a38f1a/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a90a39157/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a90a2c628/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a90a41b60/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a90a260db/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a90a260db/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a8bef1c30/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a8e4d3c90/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH ... The reason is that the hardware filter only considers the privilege level applicable to the branch target. Extend software filtering to also validate the branch-from addresses against br_sel, so that any branch record whose branch-from address is in the kernel is dropped when PERF_SAMPLE_BRANCH_USER is requested.","publishedAt":"2026-08-28T08:16:44","lastModifiedAt":"2026-08-28T08:16:44","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-80602","cvssScore":null,"cvssVector":"Pending","epssProbability":0.00168,"riskScore":0,"affectedProduct":"linux","affectedVersions":"unknown","vulnerabilityType":"Kernel","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-80602","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-80602","en":"https://www.redsauce.net/en/cves/CVE-2026-80602","fr":"https://www.redsauce.net/fr/cves/CVE-2026-80602","pt":"https://www.redsauce.net/pt/cves/CVE-2026-80602","de":"https://www.redsauce.net/de/cves/CVE-2026-80602","sk":"https://www.redsauce.net/sk/cves/CVE-2026-80602","el":"https://www.redsauce.net/el/cves/CVE-2026-80602"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-80602"}}