EUVD-2026-42188
GHSA-h655-847g-q4f7
Severity by source
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Local X connection required (AV:L, PR:L) with no victim interaction (UI:N); heap corruption in the display server yields high C/I/A and no scope change.
Primary rating from Vendor (CNA).
CVSS VectorNVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
6Description PRE-NVD
AnalysisAI
Local privilege escalation via heap buffer overflow in the X.Org Server (versions before 21.1.24) and Xwayland (before 24.1.13) allows a local user holding an X connection to corrupt heap memory by supplying a malicious PCX font. The flaw lives in the SetFont code path, where missing glyph boundary checks let an oversized or malformed glyph write past its heap allocation, yielding full confidentiality, integrity, and availability impact (CVSS 7.8). …
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Recommended ActionAI
Within 24 hours: Identify all systems running X.Org Server (versions before 21.1.24) or Xwayland (before 24.1.13) and assess exposure across desktop and development workstations. …
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A flaw was found in xorg-x11-server before 1.20.3. Rated medium severity (CVSS 6.6), this vulnerability is low attack co
"" In X.Org X Server 1.20.4, there is a stack-based buffer overflow in the function XQueryKeymap. Rated high severity (C
In the X.Org X server before 2017-06-19, a user authenticated to an X Session could crash or execute code in the context
Use-after-free in the GLX dispatch layer of X.Org X Server and Xwayland allows an authenticated X client to corrupt heap
A vulnerability was found in X.Org. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low atta
A vulnerability was found in X.Org. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low atta
A vulnerability was found in X.Org. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low atta
A vulnerability was found in X.Org. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low atta
A vulnerability was found in X.Org. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low atta
A vulnerability classified as critical was found in X.org Server. Rated high severity (CVSS 8.8), this vulnerability is
A out-of-bounds write flaw was found in the xorg-x11-server. Rated high severity (CVSS 7.8), this vulnerability is low a
A flaw was found in xorg-server. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Out-o
Same weakness CWE-122 – Heap-based Buffer Overflow
View allSame technique Buffer Overflow
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External POC / Exploit Code
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