# CVE-2026-121400: FreeRDP CPU exhaustion in RD Gateway packet handler

Source: https://junglewise.ai/threats/cve-2026-121400-freerdp-before-3-32-2-contains-a-denial-of-service-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-03. Updated: 2026-11-03  
License: CC BY 4.0 with a link back

CVE-2026-121400 · Severity: medium · CVSS 6.5 · Published 2026-11-03

FreeRDP is a remote desktop client used to connect to Windows systems and RD Gateways. A malicious RD Gateway can exhaust the client's CPU by sending a specially crafted control packet with incomplete data, causing the client to spin at 100% CPU utilization on a single thread until manually stopped. This creates a denial-of-service condition that makes the client machine unresponsive.

Technologies: [FreeRDP](https://junglewise.ai/threats/technologies/freerdp). Vendors: [FreeRDP](https://junglewise.ai/threats/vendors/freerdp).

## Quick answers

**Is CVE-2026-121400 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-121400 being exploited in the wild.

**How severe is CVE-2026-121400?** Medium severity, with a CVSS score of 6.5, published 3 November 2026.

**Which products and versions are affected?** FreeRDP before 3.32.2.

**Is there a fix for CVE-2026-121400?** Yes: fixed in 3.32.2. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-121400 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-121400?** Check whether you run 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

## Technical details

The vulnerability is an infinite loop (CWE-835) in rdg_process_control_packet when handling RD Gateway control packets. After completing the RDG tunnel-open exchange, an attacker sends an eight-byte keepalive header with packetLength=0xFFFF and withholds the body payload. The vulnerable code retries rdg_socket_read whenever BIO_should_retry returns true with no wait, backoff, or iteration limit, causing an unbounded no-progress read loop that spins one client thread at full CPU until user-requested abort is processed.

## Affected products

- FreeRDP FreeRDP before 3.32.2

## Timeline

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

## References

- [https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-x4x6-2hrm-hvq9](https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-x4x6-2hrm-hvq9)
- [https://www.vulncheck.com/advisories/freerdp-before-3.32.2-cpu-exhaustion-via-rdg-control-packet](https://www.vulncheck.com/advisories/freerdp-before-3.32.2-cpu-exhaustion-via-rdg-control-packet)

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