Multiple cross-site scripting (XSS) vulnerabilities in WebCalendar allow remote attackers to inject arbitrary web script via (1) view_entry.php, (2) view_d.php, (3) usersel.php, (4) datesel.php, (5) trailer.php, or (6) styles.php, as demonstrated using img srg tags.
CRLF injection vulnerability in login.php in WebCalendar allows remote attackers to inject CRLF sequences via the return_path parameter and perform HTTP Response Splitting attacks to modify expected HTML content from the server.
validate.php in WebCalendar allows remote attackers to gain sensitive information via an invalid encoded_login parameter, which reveals the full path in an error message.