CVE-2026-56002

A heap bufferflow in pcfReadFont() due to missing glyph bounds checking in libXfont2 before 2.0.8 allows attackers authenticated as X client to execute code within the X server.

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/lib/libxfont/-/commit/b4389e0b1d84a690b819bb27b1439968811a3674	Patch
https://www.openwall.com/lists/oss-security/2026/07/08/1	Mailing List Patch Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:x:libxfont:*:*:*:*:*:*:*:*

History

25 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Un desbordamiento de búfer de pila en pcfReadFont() debido a la falta de comprobación de límites de glifos en libXfont2 antes de 2.0.8 permite a los atacantes autenticados como cliente X ejecutar código dentro del servidor X.

Information

Published : 2026-07-08 10:16

Updated : 2026-10-25 20:10

NVD link : CVE-2026-56002

Mitre link : CVE-2026-56002

CVE.ORG link : CVE-2026-56002

JSON object : View

Products Affected

x

libxfont

CWE

CWE-122

Heap-based Buffer Overflow

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