CVE-2025-5745

A flaw was found in the strncmp glibc function optimized for the Power10 architecture. Overwriting two vector registers could disrupt program control flow, possibly leading to system instability.

No Red Hat products or offerings are affected by this vulnerability.

This vulnerability is Important rather than Moderate — due to its potential to break fundamental ABI (Application Binary Interface) guarantees, which can have far-reaching implications for system stability and security. The PowerPC64LE ABI explicitly requires that non-volatile vector registers (v20–v31) be preserved across function calls. By violating this contract, the optimized strncmp implementation in glibc 2.40+ introduces a low-level corruption risk that can cause subtle and hard-to-diagnose failures in user applications or system libraries relying on these registers. Such corruption can lead to control flow anomalies, crashes, or memory disclosure without any fault in the calling code — a particularly dangerous property.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.