myBB version 1.6.4 was distributed with an unauthorized backdoor embedded in the source code. The backdoor allowed remote attackers to execute arbitrary PHP code by injecting payloads into a specially crafted collapsed cookie. This vulnerability was introduced during packaging and was not part of the intended application logic. Exploitation requires no authentication and results in full compromise of the web server under the context of the web application.

SQL injection vulnerability in the Group Promotions module in the admin control panel in MyBB (aka MyBulletinBoard) before 1.6.18 and 1.8.x before 1.8.6 and MyBB Merge System before 1.8.6 allows remote attackers to execute arbitrary SQL commands via unspecified vectors.

The installer in MyBB before 1.8.13 allows remote attackers to execute arbitrary code by writing to the configuration file.

SQL injection vulnerability in the users data handler in MyBB (aka MyBulletinBoard) before 1.8.8 and MyBB Merge System before 1.8.8 allows remote attackers to execute arbitrary SQL commands via unspecified vectors.

MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 allow attackers to have unspecified impact via vectors related to low adminsid and sid entropy.

SQL injection vulnerability in the moderation tool in MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 might allow remote attackers to execute arbitrary SQL commands via unspecified vectors.

MyBB (aka MyBulletinBoard) before 1.8.8 and MyBB Merge System before 1.8.8 allow remote attackers to have unspecified impact via vectors related to "loose comparison false positives."

newreply.php in MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 allows remote attackers to have unspecified impact by leveraging a missing permission check.

MyBB is free and open source forum software. Prior to 1.8.40, the Contact module does not validate a redirect URL or protocol correctly, resulting in an open redirect and reflected JavaScript code injection. contact.php accepts the redirect target from the from HTTP parameter in $mybb->input['from'] or the Referer HTTP header in $SERVER['HTTPREFERER'] and passes it to redirect() without sufficient verification. A javascript: URI becomes the target of the Click here if you don't want to wait any longer link because $forceredirect is true, allowing script execution when a victim selects the link. This issue is fixed in version 1.8.40.

MyBB 1.8.32 contains a chained vulnerability that allows authenticated administrators to bypass avatar upload restrictions and execute arbitrary code. Attackers can modify upload path settings, upload a malicious PHP-embedded image file, and execute commands through the language configuration editing interface.

MyBB is free and open source forum software. Prior to 1.8.40, the user datahandler does not properly validate checkbox and multiselect profile field types, resulting in stored JavaScript code injection. UserDataHandler::verifyprofilefields() only performs the specialized validation when isarray($profilefields[$field]) is true. A non-array profilefields[fidX] value instead of the expected profilefields[fidX][] shape falls through to generic text handling and is stored without verification. The affected value is then rendered directly by member.php and inc/functionspost.php rather than processed by the MyCode parser. The uniquely identifying implementation details include inc/datahandlers/user.php. This issue is fixed in version 1.8.40.

Rejected reason: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority. This CVE was assigned on the basis that the permission system allows a limited administrator to grant privileges exceeding their own authorization scope, potentially constituting an insecure default configuration. Following a dispute, the MITRE TL-Root determined the behavior reflects documented and intended product design rather than a security vulnerability.

xmlhttp.php in MyBB (aka MyBulletinBoard) before 1.6.18 and 1.8.x before 1.8.6 and MyBB Merge System before 1.8.6 allows remote attackers to bypass intended access restrictions via vectors related to the forum password.

MyBB before 1.8.11 allows remote attackers to bypass an SSRF protection mechanism.

Multiple SQL injection vulnerabilities in MyBulletinBoard (MyBB) before 1.0 allow remote attackers to execute arbitrary SQL commands via the (1) month, (2) day, and (3) year parameters in an addevent action in calendar.php; (4) threadmode and (5) showcodebuttons in an options action in usercp.php; (6) list parameter in an editlists action to usercp.php; (7) rating parameter in a rate action in member.php; and (8) rating parameter in either showthread.php or ratethread.php.

SQL injection vulnerability in the User Inline Moderation feature in the Admin Control Panel (ACP) in MyBB (aka MyBulletinBoard) before 1.6.7 allows remote administrators to execute arbitrary SQL commands via unspecified vectors.

Multiple SQL injection vulnerabilities in calendar.php in MyBB (aka MyBulletinBoard) 1.2.5 and earlier allow remote attackers to execute arbitrary SQL commands via the (1) year or (2) month parameter. NOTE: the provenance of this information is unknown; the details are obtained solely from third party information.

SQL injection vulnerability in the createsession function in classsession.php in MyBB (aka MyBulletinBoard) 1.2.3 and earlier allows remote attackers to execute arbitrary SQL commands via the Client-IP HTTP header, as utilized by index.php, a related issue to CVE-2006-3775.

MyBB (aka MyBulletinBoard) before 1.6.18 and 1.8.x before 1.8.6 and MyBB Merge System before 1.8.6 allow remote attackers to obtain the installation path via vectors involving error log files.

MyBB (aka MyBulletinBoard) before 1.8.8 on Windows and MyBB Merge System before 1.8.8 on Windows might allow remote attackers to obtain sensitive information from ACP backups via vectors involving a short name.

MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 might allow remote attackers to obtain sensitive database information via vectors involving templates.

MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 allow remote attackers to obtain sensitive information by leveraging missing directory listing protection in upload directories.

MyBB (aka MyBulletinBoard) before 1.8.8 on Windows and MyBB Merge System before 1.8.8 on Windows allow remote attackers to overwrite arbitrary CSS files via vectors related to "style import."

SQL injection vulnerability in pages.php in Custom Pages 1.0 plugin for MyBulletinBoard (MyBB) allows remote attackers to execute arbitrary SQL commands via the page parameter.

The fetchremotefile function in MyBB (aka MyBulletinBoard) before 1.8.8 and MyBB Merge System before 1.8.8 allows remote attackers to conduct server-side request forgery (SSRF) attacks via unspecified vectors.

Cross-site request forgery (CSRF) vulnerability in usercp2.php in MyBB (aka MyBulletinBoard) before 1.4.12 allows remote attackers to hijack the authentication of unspecified victims via unknown vectors.

The Admin control panel in MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 allows remote attackers to conduct clickjacking attacks via unspecified vectors.

In MyBB before 1.8.11, the Email MyCode component allows XSS, as demonstrated by an onmouseover event.

Cross-site scripting (XSS) vulnerability in MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 might allow remote attackers to inject arbitrary web script or HTML via vectors related to login.

Cross-site scripting (XSS) vulnerability in the Admin control panel in MyBB (aka MyBulletinBoard) before 1.8.8 and MyBB Merge System before 1.8.8 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.