Exposure of Sensitive Information to an Unauthorized Actor
openwebmail.pl in Open WebMail 1.7 and 1.71 reveals sensitive information in error messages and generates different responses whether a user exists or not, which allows remote attackers to identify valid usernames via brute force attacks and obtain certain configuration and version information.
CWE-200 - Information Exposure
An information exposure vulnerability is categorized as an information flow (IF) weakness, which can potentially allow unauthorized access to otherwise classified information in the application, such as confidential personal information (demographics, financials, health records, etc.), business secrets, and the application's internal environment.