The remote web server is affected by multiple vulnerabilities.
The remote host is running ListManager, a web-based commercial mailing list management application from Lyris. According to its banner, the version of ListManager installed on the remote host relies on client-side code to validate unspecified form parameters before processing them. An attacker who is subscribed to a list managed by the affected application can reportedly leverage this issue to elevate his privileges to list administrator or gain access to arbitrary mailing lists. In addition, once administrative access has been granted, another vulnerability in ListManager's administrative interface allows creation of new accounts that collide with existing accounts, which results in overwriting data in the existing accounts.
Upgrade to version 9.3b / 9.2c / 8.95d or higher.