Improper input validation in Synapse - CVE-2018-10657

 

Improper input validation in Synapse - CVE-2018-10657

Published: May 2, 2018 / Updated: May 9, 2018


Vulnerability identifier: #VU12518
CSH Severity: Medium
CVSS v4.0: 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/E:A/U:Green
CVE-ID: CVE-2018-10657
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability: The vulnerability is being exploited in the wild
Vendor: Matrix.org
Affected software:
Synapse

Detailed vulnerability description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to an input validation error where malicious events injected with depth = 2^63 - 1 render rooms unusable, related to federation/federation_base.py and handlers/message.py. A remote attacker can send malicious messages and perform a denial of service attack.

Note: this vulnerability has been exploited in the wild in April 2018.


How to mitigate CVE-2018-10657

Update to version 0.28.1.

Sources