Heap buffer overflow in FreeRDP via license_check_stream_length
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- —
- Confidentiality · integrity · availability
- None · High · High
- Fix status
- Partial Red Hat: 1 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.
Summary
FreeRDP from 3.0.0 before 3.32.0 is affected. An integer truncation flaw in license_check_stream_length (CWE-122) causes a heap buffer overflow on 32-bit clients. A malicious RDP server can send a crafted license request, causing denial of service or remote code execution. A public exploit is linked in the references.
Written with Claude Haiku 5.5 from the sources below · 2026-11-03
Description from the CNA
FreeRDP 3.0.0 before 3.32.0 contains an integer truncation vulnerability in license_check_stream_length that allows a malicious RDP server to trigger a heap buffer overflow on 32-bit clients. Attackers can send a crafted SERVER_LICENSE_REQUEST with a large scopeCount that bypasses length checks, causing out-of-bounds writes leading to denial of service or remote code execution.
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. Red Hat gives no fix plan for Red Hat Enterprise Linux 10, which is affected.
Written with Claude Haiku 5.5 from the sources below · 2026-11-03
- 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
15 records Highest priority Priority HIGH 3 HIGH, 8 MEDIUM, 4 LOW
Other records, highest priority first
- TI-2026-71073 Double free in FreeRDP NSCodec context initializationPriority HIGH 69
- TI-2026-71061 Improper certificate validation in FreeRDP HTTP requestsPriority HIGH 68
- TI-2026-71066 Heap buffer overflow in FreeRDP PKCS#11 key enumerationPriority HIGH 66
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
- 2026-10-12 Threatist record created from CVE-2026-109255
- 2026-10-12 Alias added: GHSA-782m-c8ch-x5jc
- 2026-10-13 Affected versions changed · Red Hat
- 2026-10-13 CVSS score added · Red Hat
- 2026-10-13 Priority changed: MEDIUM → LOW
- 2026-10-13 CISA SSVC decision points changed
- 2026-10-13 Priority changed: LOW → MEDIUM
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-2026-109255 · CVE Program
- CVE-2026-109255 · NVD
- FIRST EPSS
- GHSA-782m-c8ch-x5jc · GitHub Advisory Database · CC BY 4.0
- CVE-2026-109255 · 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