CVE-2026-67291

FreeRDP before 3.29.0 Heap Out-of-Bounds Read via GLYPH_FRAGMENT_ADD

HIGH
7.5
CVSS Score
Published: August 1, 2026 at 12:22 PM UTC
Updated: September 3, 2026 at 07:44 PM UTC
1 product affected across 1 vendorFreeRDP

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Severity
HIGH7.5
Exploit prediction
EPSS 0.4%
SSVC
PoC

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 3.29.0
Vendor states this is fixed in 3.29.0 (unaffected)

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHVulnCheck
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-125

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