CVE-2026-55999

Severity CVSS v4.0:

Pending analysis

Type:

CWE-122 Heap-based Buffer Overflow

Publication date:

08/07/2026

Last modified:

09/07/2026

Description

Local attackers with a X connection able to provide PCX fonts to the X <br /> server xorg-server before 21.2.24 and xwayland before 24.1.13 could <br /> cause a heap buffer overflow via SetFont due to missing glyph boundary checks.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 8.50 HIGH
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

Attack Vector (AV): Network
Attack Complexity (AC): High
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Changed
Confidentiality (C): High
Integrity (I): High
Availability (A): High