CVE-2025-71197

Technical Description

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.

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References