Vulnerability · Published Oct 12, 2026 · Assigned by VulnCheck
CVE-2026-109246FreeRDP before 3.32.0 Shadow Server Divide-by-Zero via Frame Acknowledge PDU
Medium 6.5
In plain English
A medium-severity security flaw in FreeRDP from FreeRDP. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 35% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
FreeRDP before 3.32.0 contains a divide-by-zero vulnerability in the freerdp-shadow-cli shadow server: the frame id in a client's Frame Acknowledge PDU is stored without a range check, so the in-flight frame count in shadow_encoder_inflight_frames() can underflow. An authenticated client can acknowledge a frame id one greater than the last frame sent, causing shadow_encoder_create_frame_id() to divide by zero (SIGFPE) and terminate the process, disconnecting all viewers.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | freerdp2 | no fix listed | DEBIAN-CVE-2026-109246 |
| Debian:13 | freerdp3 | no fix listed | DEBIAN-CVE-2026-109246 |
| Debian:14 | freerdp3 | 3.32.0+dfsg-1 | DEBIAN-CVE-2026-109246 |
| Ubuntu:22.04:LTS | freerdp2 | no fix listed | UBUNTU-CVE-2026-109246 |
| Ubuntu:24.04:LTS | freerdp3 | 3.32.0+dfsg-0ubuntu0.24.04.1 | UBUNTU-CVE-2026-109246 |
| Ubuntu:26.04:LTS | freerdp3 | 3.32.0+dfsg-0ubuntu0.26.04.1 | UBUNTU-CVE-2026-109246 |
Affected products (as reported)
Weakness: CWE-191 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
References
- GitHub Security Advisory (GHSA-6vjv-4hm3-6698) vendor-advisory
- VulnCheck Advisory: FreeRDP before 3.32.0 Shadow Server Divide-by-Zero via Frame Acknowledge PDU third-party-advisory