Interpretation Conflict in Synapse - CVE-2024-53863

 

Interpretation Conflict in Synapse - CVE-2024-53863

Published: December 3, 2024 / Updated: April 23, 2026


Vulnerability identifier: #VU127000
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2024-53863
CWE-ID: CWE-436
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vendor: Matrix.org
Affected software:
Synapse

Detailed vulnerability description

The vulnerability allows a remote attacker to invoke potentially untrustworthy decoders.

The vulnerability exists due to improper restriction of processed file formats in thumbnail generation when processing a specially crafted request. A remote attacker can send a specially crafted request to invoke potentially untrustworthy decoders.

Instances with the dynamic_thumbnails option enabled are affected.


How to mitigate CVE-2024-53863

Install security update from vendor's website.

Sources