Is CVE-2026-121393 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-121393 being exploited in the wild.

How severe is CVE-2026-121393?

Medium severity, with a CVSS score of 6.5, published 3 November 2026.

Which products and versions are affected?

FreeRDP Project FreeRDP 3.0.0 to 3.32.1.

How is CVE-2026-121393 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-121393?

Check whether you run FreeRDP Project FreeRDP at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-121393: FreeRDP denial of service in RemoteFX region processing

CVE-2026-121393 · Severity: medium · CVSS 6.5 · Published 2026-11-03

FreeRDP is an open-source client for connecting to Windows Remote Desktop servers. A malicious RDP server can crash FreeRDP clients built with verbose assertions by sending specially crafted RemoteFX graphics updates, causing the client process to terminate and denying the user access to their remote session. This requires the client to be built with specific debugging features enabled and to connect to a hostile server.

Technologies: FreeRDP Project FreeRDP. Vendors: FreeRDP Project.

Quick answers

Is CVE-2026-121393 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-121393 being exploited in the wild.
How severe is CVE-2026-121393?: Medium severity, with a CVSS score of 6.5, published 3 November 2026.
Which products and versions are affected?: FreeRDP Project FreeRDP 3.0.0 to 3.32.1.
Is there a fix for CVE-2026-121393?: Yes: fixed in 3.32.2. Until then: Disable RemoteFX graphics support by not negotiating RemoteFX during RDP connection, or rebuild FreeRDP without the WITH_VERBOSE_WINPR_ASSERT=ON compile flag to tolerate the malformed packet without crashing. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-121393 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-121393?: Check whether you run FreeRDP Project FreeRDP at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: 3.32.2

Disable RemoteFX graphics support by not negotiating RemoteFX during RDP connection, or rebuild FreeRDP without the WITH_VERBOSE_WINPR_ASSERT=ON compile flag to tolerate the malformed packet without crashing.

Technical details

A crafted RemoteFX region rectangle with x coordinate set to 65535 and SurfaceBits destination left of 1 causes a 16-bit coordinate assertion overflow in rfx_process_message, terminating the client. The attack requires network connectivity to a malicious RDP server and client-side connection to that server; it does not affect data integrity, the server, or other clients. FreeRDP 3.0.0 through 3.32.1 are vulnerable when built with WITH_VERBOSE_WINPR_ASSERT=ON; FreeRDP 2.x is unaffected.

Affected products

FreeRDP Project FreeRDP 3.0.0 to 3.32.1

Timeline

2026-10-19: disclosed
2026-11-03: advisory

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.