CVE-2026-67291

FreeRDP before 3.29.0 (affected versions <= 3.28.0) contains a heap out-of-bounds read in update_process_glyph_fragments()/glyph_cache_fragment_put() in libfreerdp/cache/glyph.c. When handling a GLYPH_FRAGMENT_ADD update, the code reads a one-byte server-controlled declared fragment size but does not verify it fits within the remaining received buffer before allocating and copying that many bytes. A malicious RDP server can send a short fragment with an oversized declared size, causing the client to read beyond the allocated buffer, resulting in an out-of-bounds read and client crash.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/commit/f3b4347105114fe7453828736bea069999af319f	Patch
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-hgj8-g595-wfc6	Exploit Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-before-heap-out-of-bounds-read-via-glyph-fragment-add	Patch Third Party Advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-hgj8-g595-wfc6	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-08-01 13:16

Updated : 2026-09-03 19:33

NVD link : CVE-2026-67291

Mitre link : CVE-2026-67291

CVE.ORG link : CVE-2026-67291

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-125

Out-of-bounds Read

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