CVE-2026-67301

FreeRDP before 3.29.0 contains out-of-bounds read vulnerabilities in the async update message proxy for the PolygonSC and PolygonCB primary drawing orders. When AsyncUpdate is enabled (e.g., xfreerdp /async-update), update_message_PolygonSC() and update_message_PolygonCB() allocate a fresh points array but copy point data from the address of the order structure instead of from polygonSC->points / polygonCB->points, resulting in a client-side out-of-bounds read. A malicious or compromised RDP server sending crafted PolygonSC/PolygonCB update orders can trigger memory disclosure or a 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/5370fb26fbf034ecd11d3026b6ad639b5fff493f	Patch
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vxp3-7g6q-rq2w	Exploit Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-before-out-of-bounds-read-via-polygon-async-message-proxy	Patch Third Party Advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vxp3-7g6q-rq2w	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-08-01 13:16

Updated : 2026-09-08 14:27

NVD link : CVE-2026-67301

Mitre link : CVE-2026-67301

CVE.ORG link : CVE-2026-67301

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-125

Out-of-bounds Read

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