What is GHSA-h655-847g-q4f7?

GHSA-h655-847g-q4f7 is a security advisory published by GitHub Security Advisories with High severity. Local attackers with a X connection able to provide PCX fonts to the X server xorg-server before...

Which CVE IDs does GHSA-h655-847g-q4f7 cover?

GHSA-h655-847g-q4f7 covers the following CVE IDs: CVE-2026-55999. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of GHSA-h655-847g-q4f7?

GHSA-h655-847g-q4f7 has a CVSS v3 base score of 8.5, published by GitHub Security Advisories.

GHSA-h655-847g-q4f7HighCVSS 8.5

Local attackers with a X connection able to provide PCX fonts to the X server xorg-server before...

Vendor

GitHub Security Advisories

Published

July 8, 2026

Last Modified

July 8, 2026

🔗 CVE IDs covered (1)

CVE-2026-55999 →

📋 Description

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.

🔗 References (4)

https://nvd.nist.gov/vuln/detail/CVE-2026-55999
https://gitlab.freedesktop.org/xorg/xserver/-/commit/fbf7bac22e2c6bd627fb042742a23318263edae1
https://www.openwall.com/lists/oss-security/2026/07/08/2
https://github.com/advisories/GHSA-h655-847g-q4f7