CVE-2026-63633

Name	CVE-2026-63633
Description	FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.28.0, freerdp_dsp_decode_opus in libfreerdp/codec/dsp.c calls Stream_EnsureRemainingCapacity on context->common.buffer even though opus_decode writes decoded PCM into the caller-supplied out stream. A malicious RDP server that negotiates WAVE_FORMAT_OPUS with a client built with WITH_OPUS enabled and WITH_DSP_FFMPEG disabled can make libopus write a large decoded frame beyond the 4096-byte StreamPool_Take destination used by channels/rdpsnd/client/rdpsnd_main.c. This can corrupt the client heap, crash the client, and may permit code execution. This issue is fixed in version 3.28.0.
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)	bookworm	2.11.7+dfsg1-6~deb12u1	vulnerable
freerdp3 (PTS)	trixie	3.15.0+dfsg-2.1+deb13u3	vulnerable
	forky, sid	3.31.1+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)	3.28.0+dfsg-1

Notes

[trixie] - freerdp3 <no-dsa> (Minor issue)
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-72j9-356v-88xq
https://github.com/FreeRDP/FreeRDP/pull/12993
Fixed by: https://github.com/FreeRDP/FreeRDP/commit/0ed1f95d36913581cf31124f94eb5843d4263eae (3.28.0)