Reachable assertion in FreeRDP lets malicious servers crash clients
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 1 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-617.
Summary
FreeRDP from 3.0.0 before 3.32.2 contains a reachable assertion (CWE-617) in RemoteFX region handling. A malicious RDP server can send crafted region rectangles that trigger a 16-bit coordinate assertion, which terminates clients built with verbose WinPR assertions.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
Description from the CNA
FreeRDP from 3.0.0 before 3.32.2 contains a denial of service vulnerability that allows malicious RDP servers to abort clients built with verbose WinPR assertions by sending crafted RemoteFX region rectangles. Attackers can supply a rectangle with x set to 65535 alongside a SurfaceBits destination left of 1, triggering a 16-bit coordinate assertion in rfx_process_message that terminates the client process.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
Upgrade FreeRDP to version 3.32.2, which fixes this flaw. Red Hat lists Red Hat Enterprise Linux 10 as affected, with no fix available.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
- Fix · CNA FreeRDP (FreeRDP) Fixed in 3.32.2
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
FreeRDP 3.32.2
27 records Highest priority Priority HIGH 3 HIGH, 11 MEDIUM, 13 LOW
Other records, highest priority first
- TI-2026-84268 Denial of service in FreeRDP WinPR PNG and JPEG image readersPriority HIGH 77
- TI-2026-84291 Denial of service in FreeRDP via oversized X.224 routing tokenPriority HIGH 69
- TI-2026-84280 Use-after-free in FreeRDP dyn-channel-dump modulePriority HIGH 69
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
Not affected: 4 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-11-03 Threatist record created from CVE-2026-121393
- 2026-11-03 CISA SSVC decision points changed
- 2026-11-03 Alias added: GHSA-pmj8-2jw3-72qf
- 2026-11-04 Affected versions changed · Red Hat
- 2026-11-04 CVSS score added · Red Hat
References
More Freerdp vulnerabilities
- TI-2026-85092 Use-after-free in FreeRDP rdpgfx channel close handling CVSS 4.0CRITICAL 9.3
- TI-2026-85091 Out-of-bounds write in FreeRDP proxy via bitmap cache v2 capability CVSS 4.0CRITICAL 9.3
- TI-2026-24435 FreeRDP has a `size_t` underflow in ADPCM decoder leads to heap-buffer-overflow write CVSS 3.1CRITICAL 9.8
- TI-2023-21373 Out-Of-Bounds Write in FreeRDP CVSS 3.1CRITICAL 9.8
- TI-2022-08692 Server side NTLM does not properly check parameters in FreeRDP CVSS 3.1CRITICAL 9.1
- TI-2023-21374 Out-Of-Bounds Read in FreeRDP CVSS 3.1CRITICAL 9.1
Sources
- CVE-2026-121393 · CVE Program
- CVE-2026-121393 · NVD
- FIRST EPSS
- GHSA-pmj8-2jw3-72qf · GitHub Advisory Database · CC BY 4.0
- CVE-2026-121393 · Red Hat security data · CC BY 4.0
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