CVE-2026-80671: In the Linux kernel, the following vulnerability has been resolved: perf sched: Fix register_pid() overflow, strcpy, and BUG_ON register

In the Linux kernel, the following vulnerability has been resolved: perf sched: Fix register_pid() overflow, strcpy, and BUG_ON register_pid() has several iss

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.

Description from the National Vulnerability Database, published by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

What it means for a small business

Linux is on the computers, phones or browsers your team uses every day. Turn on automatic updates and restart: most of these fixes only take effect after a restart.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.16%, higher than 4% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

Weekly security brief

The flaws that hit local websites, every Friday.

One short email: what got exploited this week, which WordPress plugins broke, and what to check. Unsubscribe in one click.