Input validation error in Discourse - CVE-2023-40588
Published: September 13, 2023 / Updated: July 1, 2026
Vulnerability identifier: #VU136090
CSH Severity: Low
CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2023-40588
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to improper input validation in 2fa and security key name handling when processing crafted 2fa or security key names. A remote user can add a 2fa or security key with a carefully crafted name to cause a denial of service.
Affected software
Discourse
How to mitigate CVE-2023-40588
Install security update from vendor's website.
Discourse - addressed in versions 3.1.1, 3.2.0 beta1, 3.2.0 beta2