In Vanilla before 2.6.1, the polling functionality allows Insecure Direct Object Reference (IDOR) via the Poll ID, leading to the ability of a single user to select multiple Poll Options (e.g., vote for multiple items).
Multiple cross-site scripting (XSS) vulnerabilities in Vanilla Forums before 2.0.18.13 and 2.1.x before 2.1.1 allow remote attackers to inject arbitrary web script or HTML via unspecified vectors.
The edit-profile page in Vanilla Forums before 2.1a32 allows remote authenticated users to modify arbitrary profile settings by replacing the UserID value during a man-in-the-middle attack, related to a "parameter manipulation" issue.