CVE-2026-67299

FreeRDP before 3.29.0 contains a client-side heap use-after-free in the async update message proxy for WINDOW_ICON_ORDER when AsyncUpdate is enabled (e.g. xfreerdp /async-update). In update_message_WindowIcon() a shallow CopyMemory() overwrites a freshly allocated lParam->iconInfo with the parser-owned windowIcon->iconInfo pointer. After the parser callback returns, update_recv_window_info_order() frees window_icon.iconInfo, but the queued async message still retains and later dispatches that stale pointer. A malicious or compromised RDP server sending a crafted RAIL Window Alternate Secondary Order with WINDOW_ORDER_ICON can trigger use-after-free, leading to memory corruption 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/5370fb26fbf034ecd11d3026b6ad639b5fff493f	Patch
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-34hq-hwjw-q8v3	Exploit Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-before-use-after-free-via-windowicon-async-message	Patch Third Party Advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-34hq-hwjw-q8v3	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 14:32

NVD link : CVE-2026-67299

Mitre link : CVE-2026-67299

CVE.ORG link : CVE-2026-67299

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-416

Use After Free

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