CVE-2026-33977

Name	CVE-2026-33977
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.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
freerdp2 (PTS)	bullseye	2.3.0+dfsg1-2+deb11u1	vulnerable
	bullseye (security)	2.3.0+dfsg1-2+deb11u3	vulnerable
	bookworm	2.11.7+dfsg1-6~deb12u1	vulnerable
freerdp3 (PTS)	trixie	3.15.0+dfsg-2.1	vulnerable
	sid, forky	3.24.2+dfsg-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
freerdp2	source	(unstable)	(unfixed)
freerdp3	source	(unstable)	3.24.2+dfsg-1

Notes

[trixie] - freerdp3 <no-dsa> (Minor issue)
[bookworm] - freerdp2 <no-dsa> (Minor issue)
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-8f2g-3q27-6xm5