CVE-2025-71197: Linux

EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: w1: therm: Fix off-by-one buffer overflow in alarms_store The sysfs buffer passed to alarms_store() is allocated with 'size + 1' bytes and a NUL terminator is appended. However, the 'size' argument does not account for this extra byte. The original code then allocated 'size' bytes and used strcpy() to copy 'buf', which always writes one byte past the allocated buffer since strcpy() copies until the NUL terminator at index 'size'. Fix this by parsing the 'buf' parameter directly using simple_strtoll() without allocating any intermediate memory or string copying. This removes the overflow while simplifying the code.

Affected products

• Linux Linux: from 5.8, before 5.10.249 (fixed in 5.10.249); from 5.11, before 5.15.199 (fixed in 5.15.199); from 5.16, before 6.1.162 (fixed in 6.1.162); from 6.2, before 6.6.122 (fixed in 6.6.122); from 6.7, before 6.12.68 (fixed in 6.12.68); from 6.13, before 6.18.8 (fixed in 6.18.8)
• Siemens SIMATIC s7-1500 CPU 1518-4 Pn/dp Mfp: from V3.1.6
• Siemens SIMATIC s7-1500 CPU 1518f-4 Pn/dp Mfp: from V3.1.6
• Siemens Siplus s7-1500 CPU 1518-4 Pn/dp Mfp: from V3.1.6

Published 2026-02-04. Last modified 2026-07-14.