CVE-2025-5702

A flaw was found in the optimized strcmp glibc function for the Power10 CPU architecture. GNU C library versions from 2.39 onward overwrite two vector registers in a way that can disrupt the control flow of a program.

This flaw is marked as a Moderate vulnerability rather than an Important one because, while it violates the PowerPC64LE ABI by overwriting non-volatile vector registers (v20 to v31) in the optimized strcmp implementation, its impact is highly context-dependent. The vulnerability does not result in immediate memory corruption, privilege escalation, or remote code execution on its own. It only poses a risk if the overwritten registers were actively holding critical state across the call to strcmp, which is uncommon in typical usage patterns of the function. Moreover, since this issue occurs in an architecture-specific optimization path for Power10 and affects a relatively recent version of glibc (2.39+), its exposure is limited in scope and deployment.

Note that this vulnerability only impacts POWER10 (ppc64le), not POWER9, nor the aarch64, s390x, x86-64 products.

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.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.