CVE-2025-26595: redhat enterprise_linux Stack-based Buffer Overflow

Vulnerability summary

CVE-2025-26595 is a high (CVSS 7.8) Stack-based Buffer Overflow vulnerability in redhat enterprise_linux. EPSS estimates a 0.44% chance of exploitation in the next 30 days, higher than 36.6% of scored vulnerabilities.

Timeline

1. 25-02-2025
   PublishedVulnerability first disclosed.
2. 29-06-2026
   Last modifiedVulnerability information updated.

Description

A buffer overflow flaw was found in X.Org and Xwayland. The code in XkbVModMaskText() allocates a fixed-sized buffer on the stack and copies the names of the virtual modifiers to that buffer. The code fails to check the bounds of the buffer and would copy the data regardless of the size.

• CWE-121Stack-based Buffer OverflowA stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.