Reachable assertion in FreeRDP - CVE-2026-33977

 

Reachable assertion in FreeRDP - CVE-2026-33977

Published: April 8, 2026


Vulnerability identifier: #VU125372
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-33977
CWE-ID: CWE-617
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vendor: FreeRDP
Affected software:
FreeRDP

Detailed vulnerability description

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to reachable assertion in freerdp_dsp_decode_ima_adpcm() and dsp_decode_ima_adpcm_sample() in libfreerdp/codec/dsp.c when processing RDPSND IMA ADPCM audio data from a server. A remote attacker can send a specially crafted audio block with an invalid initial step index to cause a denial of service.

Audio redirection must be enabled, which is the default configuration.


How to mitigate CVE-2026-33977

Install security update from vendor's website.

Sources