Vulnerability · Published Aug 19, 2026 · Assigned by GitHub_M
CVE-2026-63117FreeRDP: Denial of service through ADPCM frame size calculation
Medium 6.5
In plain English
A medium-severity security flaw in FreeRDP from FreeRDP. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 46% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.28.0, an authenticated RDP client can advertise DVI ADPCM with nBlockAlign equal to 8 and nChannels equal to 2 to make the `bs` calculation in rdpsnd_server_select_format in channels/rdpsnd/server/rdpsnd_main.c equal zero. The subsequent out_frames modulo `bs` operation raises SIGFPE and terminates the server-side rdpsnd channel process. This vulnerability fixed in 3.28.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | freerdp2 | no fix listed | DEBIAN-CVE-2026-63117 |
| Debian:13 | freerdp3 | no fix listed | DEBIAN-CVE-2026-63117 |
| Debian:14 | freerdp3 | 3.28.0+dfsg-1 | DEBIAN-CVE-2026-63117 |
| Ubuntu:22.04:LTS | freerdp2 | no fix listed | UBUNTU-CVE-2026-63117 |
| Ubuntu:24.04:LTS | freerdp3 | 3.30.0+dfsg-0ubuntu0.24.04.1 | UBUNTU-CVE-2026-63117 |
| Ubuntu:26.04:LTS | freerdp3 | 3.30.0+dfsg-0ubuntu0.26.04.1 | UBUNTU-CVE-2026-63117 |
Affected products (as reported)
Weakness: CWE-369 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-v64m-xxfw-hrv6 x_refsource_CONFIRM
- https://github.com/FreeRDP/FreeRDP/pull/12980 x_refsource_MISC
- https://github.com/FreeRDP/FreeRDP/commit/b78fc0b138fe8f08a8b102e193ffb32986f4449a x_refsource_MISC
- https://github.com/FreeRDP/FreeRDP/releases/tag/3.28.0 x_refsource_MISC