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.
CVE-2025-26595
CVSS base score
7.8 (v3.1)
Severity
HIGH
Attack vector
Local
Weakness
CWE-121, CWE-787
Last modified
November 4, 2026
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected products
tigervnc tigervnc
x.org x server
x.org xwayland
redhat enterprise linux
References
- access.redhat.com Third Party Advisory
- access.redhat.com Third Party Advisory
- access.redhat.com Third Party Advisory
- access.redhat.com Third Party Advisory
- access.redhat.com Third Party Advisory
- access.redhat.com Third Party Advisory
- access.redhat.com Third Party Advisory
- access.redhat.com Third Party Advisory
- access.redhat.com Third Party Advisory
- access.redhat.com Third Party Advisory