Input validation error in Synapse - CVE-2024-52815
Published: December 3, 2024 / Updated: April 23, 2026
Vulnerability identifier: #VU127001
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2024-52815
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper input validation in invite validation over federation when processing invites received over federation. A remote attacker can send a specially crafted invite to cause a denial of service.
The issue can disrupt the invited user's /sync functionality.
Affected software
Synapse
Fedora
matrix-synapse
Fedora
matrix-synapse
How to mitigate CVE-2024-52815
Install security update from vendor's website.
Synapse - update to 1.120.1
matrix-synapse - addressed in versions 1.111.1-3.fc40, 1.118.0-3.fc41
matrix-synapse - addressed in versions 1.111.1-3.fc40, 1.118.0-3.fc41