CVE-2026-56003

A heap buffer overflow due to missing size checking in the property buffer when parsing PCF files in libXfont2 ComputeScaledProperties() before libXfont2 before 2.0.8 could be used by attackers using authenticated X clients 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/dff957a5158da038a282a59a31fe736702732939	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

09 Jul 2026, 19:40

Type	Values Removed	Values Added
First Time		X X libxfont
CPE		cpe:2.3:a:x:libxfont::::::::
References	~~() https://gitlab.freedesktop.org/xorg/lib/libxfont/-/commit/dff957a5158da038a282a59a31fe736702732939 -~~	() https://gitlab.freedesktop.org/xorg/lib/libxfont/-/commit/dff957a5158da038a282a59a31fe736702732939 - Patch
References	~~() https://www.openwall.com/lists/oss-security/2026/07/08/1 -~~	() https://www.openwall.com/lists/oss-security/2026/07/08/1 - Mailing List, Patch, Third Party Advisory

08 Jul 2026, 10:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-08 10:16

Updated : 2026-07-09 19:50

NVD link : CVE-2026-56003

Mitre link : CVE-2026-56003

CVE.ORG link : CVE-2026-56003

JSON object : View

Products Affected

x

libxfont

CWE

CWE-122

Heap-based Buffer Overflow

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