CVE-2026-63633

critical

FreeRDP is a free implementation of the Remote Desktop Protocol.

Vendor / product: Freerdp — freerdp

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

9.8

9.8 (CVSS v3.1)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity source: NVD CVSS v3.1 (nvd@nist.gov)

Timeline (UTC)

Published: 2026-08-19 18:17

Modified: 2026-10-26 11:10

NVD status: Analyzed

Last synced 2 days ago

Verified against the source API 2026-10-27 07:07 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

freerdp / freerdp <3.28.0

Weakness classification (CWE)

CWE-122

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Vendor advisory: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-72j9-356v-88xq

Patch / mitigation: https://github.com/FreeRDP/FreeRDP/commit/0ed1f95d36913581cf31124f94eb5843d4263eae

Patch / mitigation: https://github.com/FreeRDP/FreeRDP/pull/12993

Patch / mitigation: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-72j9-356v-88xq

References

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

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 07:07 UTC · record ↗

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CVE-2026-63633

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Weakness classification (CWE)

Mitigation & advisories

References

Data sources

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