Description
In the Linux kernel, the following vulnerability has been resolved: perf tools: Use perf_env__get_cpu_topology() in machine__resolve() machine__resolve() accesses env->cpu[al->cpu].socket_id after checking al->cpu >= 0 and env->cpu != NULL, but without validating al->cpu against env->nr_cpus_avail. Since al->cpu comes from the untrusted perf.data sample, a crafted file with a large CPU index causes an out-of-bounds heap read. Use perf_env__get_cpu_topology() which validates both NULL and bounds. Also bounds-check al->cpu before the cast to struct perf_cpu (int16_t): without this, values like 65536 silently truncate to 0, bypassing the accessor's internal check and returning CPU 0's topology.
References3
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 1% percentile: 52 · as of 8 November 2026
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.