High severity · published Jul 8, 2026
CVE-2026-56002
libXfont2 PCF Font Parsing Heap Buffer Overflow
8.8
CVSS
0.4%
EPSS
No
On KEV
Description
A heap bufferflow in pcfReadFont() due to missing glyph bounds checking in libXfont2 before 2.0.8  allows attackers authenticated as X client to execute code within the X server.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 37% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libXfont2 · X.Org
before 2.0.8 · source: vendor
LI
Libxfont · X
before 2.0.8 · source: NVD