CVE-2026-63633

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/commit/0ed1f95d36913581cf31124f94eb5843d4263eae
https://github.com/FreeRDP/FreeRDP/pull/12993
https://github.com/FreeRDP/FreeRDP/releases/tag/3.28.0
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-72j9-356v-88xq

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 18:17

Updated : 2026-09-09 21:19

NVD link : CVE-2026-63633

Mitre link : CVE-2026-63633

CVE.ORG link : CVE-2026-63633

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

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