CVE-2026-55999NVD

Vulnerability Summary

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.

Severity Level

HIGH(8.5)

Published Date

Jul 8, 2026

Last Modified

Jul 9, 2026

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

0.27%Probability

Root Weakness (CWE)

CWE-122: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v3.1 Base Metrics

Attack VectorNetwork

Attack ComplexityHigh

Privileges RequiredLow

User InteractionNone

ScopeChanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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