CVEvulnerability

CVE-2026-50256

7.8 HIGH Published 2026-06-05 Modified 2026-08-05 Official page ↗
Status
Modified
Published
2026-06-05
Last modified
2026-08-05
Assigner
[email protected]
CVSS 3.1 ([email protected])
7.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 3.1 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)
7.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weaknesses
CWE-121

Description

A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. A mismatch between the X server and the libXfont2 library's maximum font name length can cause a stack buffer overflow during font alias resolution. The server allocates a 256 byte stack buffer but libXfont2's alias target name length is 1024 bytes. A font alias name between 257 and 1023 bytes causes the X server to copy that name into the undersized stack buffer without further checks. This may be used to crash the server, or for privilege escalation if the X server runs as root.

Affected configurations

• x.org x server (< 21.1.23) • x.org xwayland (< 24.1.12) • redhat enterprise linux 7.0 • redhat enterprise linux 8.0 • redhat enterprise linux 9.0 • redhat enterprise linux 10.0

Related

Weakness · CWE (1)

  • CWE-121 Stack-based Buffer Overflow weakness

References