FreeRDP Infinite Loop via RD Gateway Chunked Response
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: 3 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-835.
Summary
FreeRDP from 2.3.0 before 3.32.0 contains an infinite loop in http_chuncked_read that lets a malicious RD Gateway hang clients. The gateway sends an incomplete chunked response, such as a partial chunk-size line or footer, followed by a clean TLS shutdown, so zero-byte reads loop forever and freeze the client decoder thread. The weakness is classified as CWE-835. CVSS 4.0 scores it 7.1 (HIGH), and the vector requires user interaction, with impact limited to availability.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Description from the CNA
FreeRDP from 2.3.0 before 3.32.0 contains an infinite loop vulnerability in http_chuncked_read that allows malicious RD Gateways to hang clients by sending incomplete chunked responses. Attackers can send a partial chunk-size line or footer followed by a clean TLS shutdown, causing zero-byte reads to loop forever and freeze the client decoder thread.
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 3.32.0 or later. Red Hat Enterprise Linux 8, 9 and 10 have no fix available yet, so Red Hat rates the issue Moderate and lists those products as affected without a fix.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
- Fix · CNA FreeRDP (FreeRDP) Fixed in 3.32.0
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
FreeRDP 3.32.0
20 records Highest priority Priority HIGH 1 HIGH, 15 MEDIUM, 4 LOW
Other records, highest priority first
- TI-2026-71718 Heap buffer over-read in FreeRDP proxy DRDYNVC channel name handlingPriority HIGH 70
- TI-2026-71714 Unbounded memory allocation in FreeRDP drive redirection readsPriority MEDIUM 64
- TI-2026-71713 Reachable assertion in FreeRDP lets a malicious server crash clientsPriority MEDIUM 64
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 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
Not affected: 2 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
Timeline
- 2026-10-13 Threatist record created from CVE-2026-109941
- 2026-10-13 Alias added: GHSA-26h4-ghv8-j876
- 2026-10-14 Priority changed: MEDIUM → LOW
- 2026-10-18 CISA SSVC decision points changed
- 2026-10-18 Priority changed: LOW → MEDIUM
- 2026-10-29 Affected versions changed · Red Hat
- 2026-10-29 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-2026-109941 · CVE Program
- CVE-2026-109941 · NVD
- FIRST EPSS
- GHSA-26h4-ghv8-j876 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-109941 · 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