FreeRDP Proxy Memory Exhaustion Flaw Rated High Severity

FreeRDP proxies are vulnerable to a memory exhaustion flaw that the National Vulnerability Database rates as high severity. The issue, tracked as CVE-2026-110833, affects FreeRDP versions from 3.0.0-beta1 up to but not including 3.32.0.

What happened

The National Vulnerability Database reports that FreeRDP fails to enforce size limits when reassembling RDPDR channel fragments. Attackers can exploit this by sending a FIRST fragment followed by continuation fragments without a terminating LAST flag. This behavior causes the proxy to grow per-session heap streams proportional to the incoming traffic volume.

As Patch Gazette reported on 2026-10-15, similar unbounded growth issues have plagued other open-source components like Eclipse Vert.x. In this specific case, the lack of cumulative or absolute size checks allows the memory consumption to rise indefinitely. The vulnerability is classified under CWE-400, indicating a resource consumption weakness.

Why it matters

The flaw allows attackers to exhaust proxy memory by sending specific fragment sequences. Because the memory growth is proportional to traffic, the resource consumption can scale with the volume of data sent. This directly impacts the available memory resources on the proxy system handling the RDPDR channel.

What to watch

• Monitor proxy memory usage for unusual spikes or steady growth patterns.
• Check network logs for RDPDR channel activity lacking proper termination flags.
• Verify current FreeRDP versions against the affected range before 3.32.0.
• Watch for vendor announcements regarding the availability of version 3.32.0.

Who needs to act first

Teams should prioritize updating exposed proxy servers that handle untrusted remote desktop traffic. Identify systems running FreeRDP versions below 3.32.0 and isolate them from networks where unauthenticated RDP connections are possible. Test any available updates in a non-production environment to ensure compatibility with existing channel configurations. Back up configuration files before applying changes to facilitate rapid rollback if stability issues arise.

What to do and how to stay safe: FreeRDP

• Inventory all systems running FreeRDP to identify those with versions prior to 3.32.0.
• Restrict inbound RDP traffic to trusted sources until a patch is confirmed available.
• Monitor system memory metrics on proxy servers for signs of abnormal growth.
• Prepare deployment plans for version 3.32.0 once the vendor releases the fix.

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General security guidance from the Patch Gazette newsroom. It is not confirmed advice from the organisations named in this story.

Frequently asked questions

Which FreeRDP versions are affected by CVE-2026-110833?

Versions from 3.0.0-beta1 up to, but not including, 3.32.0 are affected.

How is this vulnerability exploited?

Attackers send RDPDR channel fragments without a terminating LAST flag, causing unbounded memory growth.

Is there a fix available yet?

The source material indicates that versions before 3.32.0 are affected, implying 3.32.0 contains the fix.