CVE-2026-67300

FreeRDP before 3.29.0 contains client-side heap use-after-free vulnerabilities in the async update message proxy for RAIL WINDOW_STATE_ORDER and NOTIFY_ICON_STATE_ORDER when AsyncUpdate is enabled. When a malicious or compromised RDP server sends crafted update orders, the message proxy shallow-copies structures containing nested parser-owned pointers (e.g., titleInfo.string, windowRects, visibilityRects, icon buffers). The parser frees those nested buffers after the callback returns, so the queued async message later dispatches stale pointers, potentially causing memory corruption 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
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-33gg-h66j-3697
https://www.vulncheck.com/advisories/freerdp-before-use-after-free-via-async-message-proxy

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-01 13:16

Updated : 2026-08-31 20:25

NVD link : CVE-2026-67300

Mitre link : CVE-2026-67300

CVE.ORG link : CVE-2026-67300

JSON object : View

Products Affected

No product.

CWE

CWE-416

Use After Free

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