CVE-2026-67306

FreeRDP versions 3.28.0 and earlier contain an out-of-bounds read vulnerability in the RDP6 planar RLE bitmap decoder functions planar_decompress_plane_rle and planar_decompress_plane_rle_only in libfreerdp/codec/planar.c. Only the 1-byte control byte is bounds-checked; the subsequent 0–15 attacker-declared raw bytes are read without validating that the source buffer contains them. A malicious or compromised RDP server can send a truncated planar-encoded bitmap or surface update (reachable via both the Bitmap Update PDU and RDPGFX Surface Command paths) that causes the client to read past the end of the source buffer. The issue is fixed in FreeRDP 3.29.0.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/commit/5370fb26fbf034ecd11d3026b6ad639b5fff493f	Patch
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qrxx-7g3c-j6w3	Exploit Patch Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-before-out-of-bounds-read-via-planar-rle	Patch Third Party Advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qrxx-7g3c-j6w3	Exploit Patch Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-08-01 13:17

Updated : 2026-09-08 14:00

NVD link : CVE-2026-67306

Mitre link : CVE-2026-67306

CVE.ORG link : CVE-2026-67306

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-125

Out-of-bounds Read

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