CVE-2025-52576 Kanboard vulnerable to Username Enumeration via Login Behavior and Bruteforce Protection Bypass
Attackers can enumerate valid usernames and bypass IP-based brute-force protections by abusing trusted HTTP headers in Kanboard.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-52576?
CVE-2025-52576 is a medium-severity vulnerability in kanboard, published on 25 Jun 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Kanboard is project management software that focuses on the Kanban methodology. Prior to version 1.2.46, Kanboard is vulnerable to username enumeration and IP spoofing-based brute-force protection bypass. By analyzing login behavior and abusing trusted HTTP headers, an attacker can determine valid usernames and circumvent rate-limiting or blocking mechanisms. Any organization running a publicly accessible Kanboard instance is affected, especially if relying on IP-based protections like Fail2Ban or CAPTCHA for login rate-limiting. Attackers with access to the login page can exploit this flaw to enumerate valid usernames and bypass IP-based blocking mechanisms, putting all user accounts at higher risk of brute-force or credential stuffing attacks. Version 1.2.46 contains a patch for the issue.
Weakness: CWE-203
Which versions are affected by CVE-2025-52576?
It affects 1 product.
Products include Kanboard Kanboard.
How do I fix CVE-2025-52576?
No fix has been published for CVE-2025-52576 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-52576 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-52576 exists.
Other vulnerabilities in kanboard
- CVE-2026-21881 Kanboard is Vulnerable to Reverse Proxy Authentication Bypass
- CVE-2025-55010 Kanboard Authenticated Admin Remote Code Execution via Unsafe Deserialization of Events
- CVE-2024-51747 Arbitrary File Read and Delete in kanboard
- CVE-2024-51748 Remote code execution through language setting in kanboard
- CVE-2017-12850 Business logic in n/a
Sources
Also known as GHSA-qw57-7cx6-wvp7.