CVE-2025-38424: Debian Linux

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: perf: Fix sample vs do_exit() Baisheng Gao reported an ARM64 crash, which Mark decoded as being a synchronous external abort -- most likely due to trying to access MMIO in bad ways. The crash further shows perf trying to do a user stack sample while in exit_mmap()'s tlb_finish_mmu() -- i.e. while tearing down the address space it is trying to access. It turns out that we stop perf after we tear down the userspace mm; a receipie for disaster, since perf likes to access userspace for various reasons. Flip this order by moving up where we stop perf in do_exit(). Additionally, harden PERF_SAMPLE_CALLCHAIN and PERF_SAMPLE_STACK_USER to abort when the current task does not have an mm (exit_mm() makes sure to set current->mm = NULL; before commencing with the actual teardown). Such that CPU wide events don't trip on this same problem.

Affected products

• Debian Debian Linux: version 11.0 only
• Linux Linux Kernel: from 3.7, before 5.4.295 (fixed in 5.4.295); from 5.5, before 5.10.239 (fixed in 5.10.239); from 5.11, before 5.15.186 (fixed in 5.15.186); from 5.16, before 6.1.142 (fixed in 6.1.142); from 6.2, before 6.6.95 (fixed in 6.6.95); from 6.7, before 6.12.35 (fixed in 6.12.35); …

Published 2025-07-25. Last modified 2026-07-30.