Incorrect Regular Expression in Discourse - CVE-2023-23621
Published: January 30, 2023
Vulnerability identifier: #VU71617
CSH Severity: High
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-2023-23621
CWE-ID: CWE-185
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient input validation when processing regular expressions. A remote attacker can use a specially crafted user agent and perform regular expression denial of service (ReDos) attack.
Affected software
Discourse
How to mitigate CVE-2023-23621
Install update from vendor's website.
Discourse - addressed in versions 3.0.1 beta, 3.1.0 beta2