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
Affects freerdpSource GCVE Database
Not known to be exploited · CVSS 7.5 High : upgrade to 3.29.0 soon.
Data as of 31 Oct 2026, 08:20 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 25% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.29.0
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 1 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade freerdp/FreeRDP to 3.29.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
GitHubfreerdp/FreeRDPpkg:github/freerdp/FreeRDPOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, consider disabling AsyncUpdate if feasible to reduce exposure to this vulnerability.
Description
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.
References
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-33gg-h66j-3697 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-67300 (opens in a new tab)
- github.com/FreeRDP/FreeRDP/commit/5370fb26fbf034ecd11d3026b6ad639b5fff493f (opens in a new tab)
- vulncheck.com/advisories/freerdp-before-use-after-free-via-async-message-proxy (opens in a new tab)
- ubuntu.com/security/CVE-2026-67300 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-67300 (opens in a new tab)