register.php in Ultimate PHP Board (UPB) 1.0 and 1.0b uses an administrative account Admin with a capital "A," but allows a remote attacker to impersonate the administrator by registering an account name of admin with a lower case "a."

References

• https://nvd.nist.gov/vuln/detail/CVE-2002-1820
• http://www.iss.net/security_center/static/9972.php
• http://www.securityfocus.com/archive/1/289417
• http://www.securityfocus.com/bid/5580