CVE-2026-33977 (GCVE-0-2026-33977)

Vulnerability from cvelistv5 – Published: 2026-03-30 21:41 – Updated: 2026-03-31 19:09
VLAI
Title
FreeRDP: DoS via WINPR_ASSERT in IMA ADPCM audio decoder (dsp.c:331)
Summary
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.
Severity
6.9 (Medium)
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
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-31 18:38 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
FreeRDP FreeRDP Affected: < 3.24.2
guessed Create a notification for this product.
Show details on NVD website
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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