An issue was discovered in MantisBT before 2.24.4. Due to insufficient access-level checks, any logged-in user allowed to perform Group Actions can get access to the Summary fields of private Issues via bug_arr[]= in a crafted bug_actiongroup_page.php URL. (The target Issues can have Private view status, or belong to a private Project.)
An issue was discovered in MantisBT before 2.24.4. An incorrect access check in bug_revision_view_page.php allows an unprivileged attacker to view the Summary field of private issues, as well as bugnotes revisions, gaining access to potentially confidential information via the bugnote_id parameter.
An issue was discovered in MantisBT before 2.24.3. When editing an Issue in a Project where a Custom Field with a crafted Regular Expression property is used, improper escaping of the corresponding form input's pattern attribute allows HTML injection and, if CSP settings permit, execution of arbitrary JavaScript.
An issue was discovered in file_download.php in MantisBT before 2.24.3. Users without access to view private issue notes are able to download the (supposedly private) attachments linked to these notes by accessing the corresponding file download URL directly.
An issue was discovered in MantisBT before 2.24.3. Improper escaping of a custom field's name allows an attacker to inject HTML and, if CSP settings permit, achieve execution of arbitrary JavaScript when attempting to update said custom field via bug_actiongroup_page.php.
An XSS issue was discovered in MantisBT before 2.24.2. Improper escaping on view_all_bug_page.php allows a remote attacker to inject arbitrary HTML into the page by saving it into a text Custom Field, leading to possible code execution in the browser of any user subsequently viewing the issue (if CSP settings allow it).
The proj_doc_edit_page.php Project Documentation feature in MantisBT before 2.21.3 has a stored cross-site scripting (XSS) vulnerability, allowing execution of arbitrary code (if CSP settings permit it) after uploading an attachment with a crafted filename. The code is executed when editing the document's page.
MantisBT 1.2.x before 1.2.2 insecurely handles attachments and MIME types. Arbitrary inline attachment rendering could lead to cross-domain scripting or other browser attacks.