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CVE-2026-55564

FreeRDP: Out-of-bounds read in glyph_cache_get via crafted glyph fragments

Published: Aug 19, 2026Updated: Aug 25, 2026 Sources: CVE List NVDCWE-125
5.4MEDIUM
NVD MITRE
EPSS Score
0.3%
Top 81.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
No Fix Available
Self-Check
OpenVAS

Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, the glyph_cache_get function in libfreerdp/cache/glyph.c checks whether index is greater than cache->number instead of greater than or equal to it. A malicious RDP server can use GLYPH_FRAGMENT_USE replay in update_process_glyph_fragments to make the default cache receive index 254 when cache->number is 254, reading one pointer beyond the entries array and dereferencing it as a glyph. This can crash the client and may disclose adjacent heap data. This issue is fixed in version 3.27.0.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:RS:UC:LI:NA:L
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:UScope
Unchanged
Impact
C:LConfidentiality
Low
I:NIntegrity
None
A:LAvailability
Low
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Weaknesses

CWE-125CWE-193

Affected Products

FreeRDP
oss-project·US
FreeRDP
OSS Libraries

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Collection
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References

https://github.com/FreeRDP/FreeRDP/commit/c29324750e3cbcba8761f147b7a5235cc686930f
github.com
https://github.com/FreeRDP/FreeRDP/pull/12885
github.com
https://github.com/FreeRDP/FreeRDP/releases/tag/3.27.0
github.com
and 1 more references View all →

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