CVE-2026-34085

fontconfig before 2.17.1 has an off-by-one error in allocation during sfnt capability handling, leading to a one-byte out-of-bounds write, and potentially a crash or code execution. This is in FcFontCapabilities in fcfreetype.c.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.5 / Impact : 3.4

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://gitlab.freedesktop.org/fontconfig/fontconfig/-/commit/b9bec06d73340f1b5727302d13ac3df307b7febc	Patch
https://gitlab.freedesktop.org/fontconfig/fontconfig/-/merge_requests/446	Patch
https://gitlab.freedesktop.org/fontconfig/fontconfig/-/work_items/481	Issue Tracking

Configurations

Configuration 1 (hide)

cpe:2.3:a:fontconfig_project:fontconfig:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-25 17:17

Updated : 2026-03-27 21:39

NVD link : CVE-2026-34085

Mitre link : CVE-2026-34085

CVE.ORG link : CVE-2026-34085

JSON object : View

Products Affected

fontconfig_project

fontconfig

CWE

CWE-193

Off-by-one Error

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