FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, a malicious RDP server can crash the FreeRDP client by sending audio data in IMA ADPCM format with an invalid initial step index value (>= 89). The unvalidated step index is read directly from the network and used to index into a 89-entry lookup table, triggering a WINPR_ASSERT() failure and process abort via SIGABRT. This affects any FreeRDP client that has audio redirection (RDPSND) enabled, which is the default configuration. This issue has been patched in version 3.24.2.
History

Wed, 01 Apr 2026 02:15:00 +0000

Type Values Removed Values Added
First Time appeared Freerdp
Freerdp freerdp
Weaknesses CWE-1285
Vendors & Products Freerdp
Freerdp freerdp
References
Metrics threat_severity

None

cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Tue, 31 Mar 2026 19:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 31 Mar 2026 03:00:00 +0000

Type Values Removed Values Added
Description FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, a malicious RDP server can crash the FreeRDP client by sending audio data in IMA ADPCM format with an invalid initial step index value (>= 89). The unvalidated step index is read directly from the network and used to index into a 89-entry lookup table, triggering a WINPR_ASSERT() failure and process abort via SIGABRT. This affects any FreeRDP client that has audio redirection (RDPSND) enabled, which is the default configuration. This issue has been patched in version 3.24.2.
Title FreeRDP: DoS via WINPR_ASSERT in IMA ADPCM audio decoder (dsp.c:331)
Weaknesses CWE-617
References
Metrics cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-03-31T19:09:29.001Z

Reserved: 2026-03-24T22:20:06.210Z

Link: CVE-2026-33977

cve-icon Vulnrichment

Updated: 2026-03-31T19:06:03.417Z

cve-icon NVD

Status : Received

Published: 2026-03-30T22:16:19.117

Modified: 2026-03-31T20:16:27.917

Link: CVE-2026-33977

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-03-30T21:41:36Z

Links: CVE-2026-33977 - Bugzilla