MyBB 1.8.31 has a (issue 2 of 2) cross-site scripting (XSS) vulnerabilities in the post Attachments interface allow attackers to inject HTML by persuading the user to upload a file with specially crafted name
MyBB 1.8.31 has a SQL injection vulnerability in the Admin CP's Users module allows remote authenticated users to modify the query string via direct user input or stored search filter settings.
MyBB 1.8.31 has a Cross-site scripting (XSS) vulnerability in the visual MyCode editor (SCEditor) allows remote attackers to inject HTML via user input or stored data
MyBB is a free and open source forum software. The _Mail Settings_ → Additional Parameters for PHP's mail() function mail_parameters setting value, in connection with the configured mail program's options and behavior, may allow access to sensitive information and Remote Code Execution (RCE). The vulnerable module requires Admin CP access with the `_Can manage settings?_` permission and may depend on configured file permissions. MyBB 1.8.31 resolves this issue with the commit `0cd318136a`. Users are advised to upgrade. There are no known workarounds for this vulnerability.