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… (CVE-2026-67300)
FreeRDP versions before 3.29.0 contain client-side heap use-after-free vulnerabilities in the asynchronous update message proxy handling RAIL WINDOW_STATE_ORDER and NOTIFY_ICON_STATE_ORDER when AsyncUpdate is enabled. These vulnerabilities arise because the message proxy shallow-copies structures with nested pointers that are freed prematurely, leading to stale pointer dereferences. This can cause memory corruption or client crashes when processing crafted update orders from a malicious or compromised RDP server. The CVSS score is 7.5, indicating high severity due to the potential for denial of service via client crash. No patch information is currently provided.
AI Analysis
Technical Summary
The vulnerability in FreeRDP before version 3.29.0 involves client-side heap use-after-free conditions in the asynchronous update message proxy for RAIL WINDOW_STATE_ORDER and NOTIFY_ICON_STATE_ORDER messages when AsyncUpdate is enabled. The message proxy shallow-copies structures containing nested parser-owned pointers such as titleInfo.string, windowRects, visibilityRects, and icon buffers. After the callback returns, the parser frees these nested buffers, but the queued asynchronous message later dispatches with stale pointers, potentially causing memory corruption or client crashes. This vulnerability is tracked as CVE-2026-67300 and is classified under CWE-416 (Use After Free). The CVSS v3.1 score is 7.5 (High), with network attack vector, low attack complexity, no privileges required, no user interaction, and impact limited to availability (client crash). There are no known exploits in the wild and no patch or remediation details currently available.
Potential Impact
Successful exploitation can cause memory corruption or crash the FreeRDP client, resulting in denial of service. There is no indication of confidentiality or integrity impact. The vulnerability requires a malicious or compromised RDP server to send crafted update orders with AsyncUpdate enabled on the client side.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, consider disabling AsyncUpdate if feasible to reduce exposure to this vulnerability. Monitor official FreeRDP channels for updates and patches addressing 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… (CVE-2026-67300)
Description
FreeRDP versions before 3.29.0 contain client-side heap use-after-free vulnerabilities in the asynchronous update message proxy handling RAIL WINDOW_STATE_ORDER and NOTIFY_ICON_STATE_ORDER when AsyncUpdate is enabled. These vulnerabilities arise because the message proxy shallow-copies structures with nested pointers that are freed prematurely, leading to stale pointer dereferences. This can cause memory corruption or client crashes when processing crafted update orders from a malicious or compromised RDP server. The CVSS score is 7.5, indicating high severity due to the potential for denial of service via client crash. No patch information is currently provided.
CVSS v3.1
Score 7.5high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in FreeRDP before version 3.29.0 involves client-side heap use-after-free conditions in the asynchronous update message proxy for RAIL WINDOW_STATE_ORDER and NOTIFY_ICON_STATE_ORDER messages when AsyncUpdate is enabled. The message proxy shallow-copies structures containing nested parser-owned pointers such as titleInfo.string, windowRects, visibilityRects, and icon buffers. After the callback returns, the parser frees these nested buffers, but the queued asynchronous message later dispatches with stale pointers, potentially causing memory corruption or client crashes. This vulnerability is tracked as CVE-2026-67300 and is classified under CWE-416 (Use After Free). The CVSS v3.1 score is 7.5 (High), with network attack vector, low attack complexity, no privileges required, no user interaction, and impact limited to availability (client crash). There are no known exploits in the wild and no patch or remediation details currently available.
Potential Impact
Successful exploitation can cause memory corruption or crash the FreeRDP client, resulting in denial of service. There is no indication of confidentiality or integrity impact. The vulnerability requires a malicious or compromised RDP server to send crafted update orders with AsyncUpdate enabled on the client side.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, consider disabling AsyncUpdate if feasible to reduce exposure to this vulnerability. Monitor official FreeRDP channels for updates and patches addressing CVE-2026-67300.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-hp6g-g26j-5q54
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-67300"]
- Ecosystems
- []
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6a6e6296bf32cb7a344f6a10
Added to database: 08/01/2026, 21:18:14 UTC
Last enriched: 08/01/2026, 21:23:34 UTC
Last updated: 08/02/2026, 03:01:34 UTC
Views: 3
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