CVE-2026-80671
CriticalCVSS 9.3Exploitation Probability (EPSS)
Low risk8th percentile - higher than 8% of all known CVEs
Summary
In the perf sched tool in the Linux kernel, register_pid() has several issues when processing untrusted perf.data: integer overflow, heap buffer overflow via strcpy, BUG_ON on allocation failure, and memory leak on realloc. The fix caps pid, uses strlcpy, adds NULL checks, and uses safe realloc patterns.
Risk Assessment
The vulnerability could allow an attacker to execute code or cause crashes in the perf tool, potentially leading to system security compromise, especially when perf is used with untrusted data.
Recommendation
Update perf tools to a version containing the fixes. Avoid processing untrusted perf.data files until patches are applied.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: perf sched: Fix register_pid() overflow, strcpy, and BUG_ON register_pid() has several issues when processing untrusted perf.data: 1. Integer overflow: (pid + 1) * sizeof(struct task_desc *) can wrap to a small value on 32-bit systems when pid is large (e.g. 0x40000000), causing realloc to return a tiny buffer followed by out-of-bounds writes in the initialization loop. 2. Heap buffer overflow: strcpy(task->comm, comm) copies the untrusted comm string into a fixed 20-byte COMM_LEN buffer with no length check. 3. BUG_ON on allocation failure: perf.data is untrusted input, so allocation failures should be handled gracefully rather than killing the process. 4. Realloc of sched->tasks assigned directly back, leaking the old pointer on failure; nr_tasks incremented before the realloc, leaving corrupted state on failure. Cap pid at PID_MAX_LIMIT (4194304, matching the kernel's maximum on 64-bit), replace strcpy with strlcpy, guard against NULL comm, replace BUG_ON with NULL returns using safe realloc patterns, and add NULL checks in callers that dereference the result.