CVE-2026-24677: FreeRDP has a heap-buffer-overflow in ecam_encoder_compress_h264

Severity: critical (CVSS 9.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-02-09 · updated 2026-06-17
Weakness: CWE-416

Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.22.0, ecam_encoder_compress_h264 trusts server-controlled dimensions and does not validate the source buffer size, leading to an out-of-bounds read in sws_scale. This vulnerability is fixed in 3.22.0.

Affected products

FreeRDP: before 3.22.0 — fixed in 3.22.0

How to fix

Upgrade to a fixed version: FreeRDP 3.22.0. Check the vendor advisory for mitigations.

References

https://github.com/FreeRDP/FreeRDP/commit/d2d4f449312ddafd4a4c6c8a4f856c7f0d44a3b5
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-xw37-j744-f8v7

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