FreeRDP before 3.32.2 Use-After-Free via RDPGFX ResetGraphics Race
FreeRDP builds before 3.32.2 are affected when a connected RDP server concurrently sends RDPGFX ResetGraphics and compressed bitmaps at 32 bpp or more, in the default configuration. Fixed in 3.32.2.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- Proof of concept public, per CISA
- Fix
- Fixed in 3.32.2
- Who is exposed
- Default setups
Do first: Check every install: default setups are affected.
- Exploitation15/40CISA rates a proof of concept as public
- Exposure25/25Default setups, CISA rates it automatable
- Reach?/20Reach: unknown (data gap). No tracked technology or package matched
- Severity8.7/10CVSS 8.7
- No patch0/5No signal
What would change the score
- Would score about 74 if added to CISA KEV
- Would score about 69 if CISA's SSVC rates exploitation active
CVE-2026-121957 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.
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- Published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 49/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Default setups
- Fix
- Fixed in 3.32.2
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: poc
- Automatable: yes
- Technical impact: partial
Summary
FreeRDP versions before the fixed release contain a use-after-free bug in the RDPGFX graphics handling that lets a malicious RDP server corrupt client memory. The flaw can be reached remotely, without logging in or any user action, by a server that races a graphics reset against compressed bitmap processing.
Read the original description
FreeRDP before 3.32.2 contains a use-after-free vulnerability that allows malicious RDP servers to corrupt client memory by racing the RDPGFX ResetGraphics handler against the planar bitmap decoder. Attackers can send ResetGraphics while concurrently sending compressed bitmaps of 32 bpp or more to trigger heap use-after-free or out-of-bounds read/write on shared planar buffers.
What to do
Check every install: default setups are affected.
Upgrade to a fixed version: 3.32.2.
Timeline
- CVE published
- First seen by cve.now
- CISA SSVC assessment
Exploitation: poc · Automatable: yes · Technical impact: partial
- Record last updated
Affected versions
- FreeRDP FreeRDP
fixed in 3.32.2
Evidence 2
- Advisory
- Link
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-121957
Is CVE-2026-121957 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: cve.now feed data
What does this mean?
A race between an RDPGFX ResetGraphics message and compressed bitmap handling can free client memory that is still in use, causing heap use-after-free or out-of-bounds reads and writes that corrupt the FreeRDP client process heap.Source: vulncheck.com, github.com
Which versions are affected by CVE-2026-121957?
FreeRDP: before 3.32.2.Source: cve.now feed data
Am I affected, and how do I check?
All FreeRDP builds before 3.32.2 are in scope. The bug requires a client that has completed the RDP handshake and is in the ACTIVE state, with a server sending RDPGFX ResetGraphics alongside legacy or fastpath compressed bitmaps at 32 bpp or more. To check, compare your installed FreeRDP version with 3.32.2.Source: vulncheck.com, github.com
How do I fix CVE-2026-121957?
Upgrade FreeRDP to 3.32.2 or later, which contains the fix. No workaround is listed in the facts.Source: vulncheck.com, github.com