CVE-2026-55999

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

CVSS v3 8.5 HIGH

8.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://gitlab.freedesktop.org/xorg/xserver/-/commit/fbf7bac22e2c6bd627fb042742a23318263edae1	Patch
https://www.openwall.com/lists/oss-security/2026/07/08/2	Mailing List Patch Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:x.org:x_server::::::::
	cpe:2.3:a:x.org:xwayland::::::::

History

09 Jul 2026, 19:49

Type	Values Removed	Values Added
CPE		cpe:2.3:a:x.org:xwayland:::::::: cpe:2.3:a:x.org:x_server::::::::
References	~~() https://gitlab.freedesktop.org/xorg/xserver/-/commit/fbf7bac22e2c6bd627fb042742a23318263edae1 -~~	() https://gitlab.freedesktop.org/xorg/xserver/-/commit/fbf7bac22e2c6bd627fb042742a23318263edae1 - Patch
References	~~() https://www.openwall.com/lists/oss-security/2026/07/08/2 -~~	() https://www.openwall.com/lists/oss-security/2026/07/08/2 - Mailing List, Patch, Third Party Advisory
First Time		X.org xwayland X.org X.org x Server

08 Jul 2026, 09:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-08 09:16

Updated : 2026-07-09 19:49

NVD link : CVE-2026-55999

Mitre link : CVE-2026-55999

CVE.ORG link : CVE-2026-55999

JSON object : View

Products Affected

x.org

x_server
xwayland

CWE

CWE-122

Heap-based Buffer Overflow

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