CVE-2026-109255 FreeRDP 3.0.0 before 3.32.0 heap buffer overflow via license_check_stream_length
A malicious RDP server can trigger a heap buffer overflow in FreeRDP clients, potentially leading to remote code execution or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-109255?
CVE-2026-109255 is a medium-severity memory corruption vulnerability in FreeRDP, published on 12 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-122
Which versions are affected by CVE-2026-109255?
How do I fix CVE-2026-109255?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-109255 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109255 exists.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as DEBIAN-CVE-2026-109255, GHSA-782m-c8ch-x5jc, GHSA-hxw3-57rq-3v4m, UBUNTU-CVE-2026-109255.