CVE-2026-109242 FreeRDP before 3.0.0 and 3.6.0 before 3.32.0 Uninitialized Heap Disclosure via Progressive Codec Tile Upgrade
A malicious RDP server can leak uninitialized heap memory or crash the FreeRDP client by sending crafted progressive tile sequences.
- 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-2026-109242?
CVE-2026-109242 is a high-severity 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 before 3.0.0 and 3.6.0 before 3.32.0 renders uninitialized heap memory from un-decoded progressive tiles because the tile->current buffer is allocated without zeroing. A malicious RDP server can send a crafted WBT_TILE_FIRST then WBT_TILE_UPGRADE sequence to paint heap bytes onscreen or abort the client process.
Weakness: CWE-908
Which versions are affected by CVE-2026-109242?
How do I fix CVE-2026-109242?
Upgrade to a fixed version.
Is CVE-2026-109242 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109242 exists.
Sources
Also known as CLSA-2026-1792155691, CLSA-2026-1792157679, DEBIAN-CVE-2026-109242, GHSA-4mpr-hmqx-83q8, GHSA-wx7m-cfxv-x2x7, UBUNTU-CVE-2026-109242.