Inefficient regular expression complexity in Mastodon - #VU126976
Published: September 30, 2024 / Updated: April 23, 2026
Vulnerability identifier: #VU126976
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: N/A
CWE-ID: CWE-1333
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 inefficient regular expression complexity in regular expressions when processing specifically crafted queries. A remote attacker can send specifically crafted queries to cause a denial of service.
This does not affect servers running on Ruby 3.3.
Affected software
Mastodon
Remediation
Install security update from vendor's website.
Mastodon - addressed in versions 4.1.20, 4.2.13