CVE-2026-67299
Received Received - Intake

Heap Use-After-Free in FreeRDP Client

Vulnerability report for CVE-2026-67299, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-08-01

Last updated on: 2026-08-01

Assigner: VulnCheck

Description

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 Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-08-01
Last Modified
2026-08-01
Generated
2026-08-01
AI Q&A
2026-08-01
EPSS Evaluated
N/A
NVD
EUVD

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
freerdp freerdp to 3.29.0 (exc)

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-416 The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

FreeRDP before version 3.29.0 has a client-side heap use-after-free vulnerability in the async update message proxy for WINDOW_ICON_ORDER when AsyncUpdate is enabled. A malicious RDP server can send a crafted RAIL Window Alternate Secondary Order with WINDOW_ORDER_ICON to trigger memory corruption and crash the client.

Detection Guidance

This vulnerability is specific to FreeRDP versions before 3.29.0. To detect it, check the installed FreeRDP version using commands like 'xfreerdp --version' or 'apt list --installed | grep freerdp'. If the version is below 3.29.0, the system is vulnerable.

Impact Analysis

This vulnerability can cause memory corruption and client crashes when connecting to a malicious or compromised RDP server. It may lead to denial of service or potential arbitrary code execution on the client system.

Mitigation Strategies

Upgrade FreeRDP to version 3.29.0 or later immediately. Disable the /async-update flag in xfreerdp if used. Avoid connecting to untrusted RDP servers until patched.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-67299. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart