Denial of service in FreeRDP shadow server via remdesk channel
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 5 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.
Summary
FreeRDP before 3.32.2 contains a denial of service flaw in the shadow server's remdesk_server_thread. An inverted PDU length check is improper input validation (CWE-20). An authenticated client can crash the server process, which aborts the server and drops sessions.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
Description from the CNA
FreeRDP before 3.32.2 contains a denial of service vulnerability in the shadow server's remdesk_server_thread that allows authenticated clients to crash the process via an inverted PDU length check. Attackers can send an 8192-byte remdesk payload declaring an eight-byte PDU length to trigger a fatal Stream_Seek assertion, aborting the server and dropping sessions.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
Update FreeRDP to version 3.32.2. Red Hat rates this Moderate and lists Red Hat Enterprise Linux 6 as affected with no fix planned, and Red Hat Enterprise Linux 7, 8, 9 and 10 as affected with the plan none 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 |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
Timeline
- 2026-11-03 Threatist record created from CVE-2026-121407
- 2026-11-03 Alias added: GHSA-m4pj-hpxh-pqp3
- 2026-11-04 Affected versions changed · Red Hat
- 2026-11-04 CVSS score added · Red Hat
- 2026-11-05 Priority changed: MEDIUM → LOW
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-2026-121407 · CVE Program
- CVE-2026-121407 · NVD
- FIRST EPSS
- GHSA-m4pj-hpxh-pqp3 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-121407 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences