Fluxbb 1.5.11 is affected by a denial of service (DoS) vulnerability by sending an extremely long password via the user login form. When a long password is sent, the password hashing process will result in CPU and memory exhaustion on the server.

References

• https://nvd.nist.gov/vuln/detail/CVE-2020-28873
• https://www.acunetix.com/vulnerabilities/web/long-password-denial-of-service/#:~:text=By%20sending%20a%20very%20long,a%20vulnerable%20password%20hashing%20implementation
• http://fluxbb.com