# CVE-2026-121957: FreeRDP use-after-free in planar bitmap decoder

Source: https://junglewise.ai/threats/cve-2026-121957-freerdp-before-3-32-2-contains-a-use-after-free-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-04. Updated: 2026-11-04  
License: CC BY 4.0 with a link back

CVE-2026-121957 · Severity: high · CVSS 7.5 · Published 2026-11-04

FreeRDP is a remote desktop client that connects to Windows RDP servers. A malicious RDP server can exploit a race condition to corrupt memory in the FreeRDP client process, potentially leading to client crashes or code execution. The vulnerability requires the server to be in an active session and exploits timing differences between concurrent operations.

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

## Quick answers

**Is CVE-2026-121957 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-121957 being exploited in the wild.

**How severe is CVE-2026-121957?** High severity, with a CVSS score of 7.5, published 4 November 2026.

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

**Is there a fix for CVE-2026-121957?** 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-2026-121957 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-121957?** 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 a use-after-free / race condition in the planar bitmap decoder (libfreerdp/codec/planar.c) where the RDPGFX ResetGraphics handler on the drdynvc thread can concurrently reset shared planar context buffers (pTempData, planesBuffer) while the main thread's planar bitmap decoder is actively reading/writing to them. No synchronization lock protects access to the BITMAP_PLANAR_CONTEXT across these threads. A remote attacker in the ACTIVE RDP session state can interleave ResetGraphics PDUs with 32+ bpp compressed bitmap updates to trigger heap corruption.

## Affected products

- FreeRDP FreeRDP before 3.32.2

## Timeline

- 2026-10-20: disclosed
- 2026-11-04: advisory

## References

- [https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-xjhw-2r55-m95g](https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-xjhw-2r55-m95g)
- [https://www.vulncheck.com/advisories/freerdp-before-3.32.2-use-after-free-via-rdpgfx-resetgraphics-race](https://www.vulncheck.com/advisories/freerdp-before-3.32.2-use-after-free-via-rdpgfx-resetgraphics-race)

## Related threats

- [FreeRDP heap use-after-free in brush cache](https://junglewise.ai/threats/cve-2026-125394-freerdp-before-3-33-0-contains-a-heap-use-after-free)
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- [FreeRDP use-after-free in dynamic rdpsnd channel](https://junglewise.ai/threats/cve-2026-121963-freerdp-before-3-32-2-contains-a-use-after-free-vulnerability-in)
- [FreeRDP denial of service in NLA shadow server via malformed TSRequest](https://junglewise.ai/threats/cve-2026-121960-freerdp-before-3-32-2-contains-a-denial-of-service-vulnerability)
- [FreeRDP heap out-of-bounds write in RDPGFX HashTable_GetKeys](https://junglewise.ai/threats/cve-2026-121958-freerdp-through-3-32-1-has-a-heap-out-of-bounds-write-in-the)