7.5
HIGH CVSS 4.0
CVE-2026-67299
FreeRDP before 3.29.0 Use-After-Free via WindowIcon async message
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.

INFO

Published Date :

Aug. 1, 2026, 1:16 p.m.

Last Modified :

Aug. 1, 2026, 1:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-67299 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH MITRE-CVE
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Update FreeRDP to version 3.29.0 or later to fix memory corruption.
  • Update FreeRDP to version 3.29.0 or later.
  • Disable AsyncUpdate if updating is not possible.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-67299 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-67299 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-67299 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-67299 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 01, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'FreeRDP', 'product': 'FreeRDP', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.29.0', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '3.29.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}]
    Added 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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-416
    Added Reference https://github.com/FreeRDP/FreeRDP/commit/5370fb26fbf034ecd11d3026b6ad639b5fff493f
    Added Reference https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-34hq-hwjw-q8v3
    Added Reference https://www.vulncheck.com/advisories/freerdp-before-use-after-free-via-windowicon-async-message
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.