Description
The strncmp implementation optimized for the Power10 processor in the GNU C Library version 2.40 and later writes to vector registers v20 to v31 without saving contents from the caller (those registers are defined as non-volatile registers by the powerpc64le ABI), resulting in overwriting of its contents and potentially altering control flow of the caller, or leaking the input strings to the function to other parts of the program.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| The GNU C Library | glibc | 2.40 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | glibc | 2.41-9 | — |
| Debian 13 | glibc | 2.41-9 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | glibc | 2.39-0ubuntu8.5 | USN-7634-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | glibc | 2.41-3.1 | openSUSE-SU-2025:15222-1 |
Advisories 3
- USN-7634-1 glibc vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- openSUSE-SU-2025:15222-1 glibc-2.41-3.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- WID-SEC-2025-1252 GNU libc: Mehrere Schwachstellen ermöglichen Manipulation von Daten BSI CERT-Bund (WID) · Dec 2, 2025