EUVD-2026-61021

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'...

CVE-2026-45118

MyBB's contact.php passes unvalidated from parameter or Referer header to redirect() without protocol checks, allowing a javascript: URI to become a clickable link that executes script when a victim clicks it. No public exploitation evidence is available. Upgrade to MyBB 1.8.40 to fix.

CVE-2026-45117 MyBB: Installer database configuration RCE

MyBB is free and open source forum software. From 1.8.13 until 1.8.40, the installer module does not properly escape user-supplied database configuration values written to the configuration file, resulting in PHP code injection and remote code execution when the installer is available...

EUVD-2026-61020

MyBB is free and open source forum software. From 1.8.13 until 1.8.40, the installer module does not properly escape user-supplied database configuration values written to the configuration file, resulting in PHP code injection and remote code execution when the installer is available...

CVE-2026-45117

MyBB 1.8.13 through 1.8.39's installer module (install/index.php) uses addcslashes() without including backslash in the character list, letting crafted database config values escape the generated PHP string for code injection and RCE. Fixed in 1.8.40; no in-the-wild exploitation reported.

CVE-2026-45117

MyBB is free and open source forum software. From 1.8.13 until 1.8.40, the installer module does not properly escape user-supplied database configuration values written to the configuration file, resulting in PHP code injection and remote code execution when the installer is available...

EUVD-2026-61019

MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP Recovery Codes module does not validate requests correctly, allowing same-site attackers to rotate a victim administrator's recovery codes with a specially crafted URL. The Admin CP Home, Preferences, Recovery Codes...

CVE-2026-45129 MyBB: ACP Recovery Codes CSRF

MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP Recovery Codes module does not validate requests correctly, allowing same-site attackers to rotate a victim administrator's recovery codes with a specially crafted URL. The Admin CP Home, Preferences, Recovery Codes...

CVE-2026-45129

In MyBB versions prior to 1.8.40, the Admin CP Recovery Codes module at admin/modules/home/preferences.php regenerates 2FA recovery codes on GET requests without CSRF protection, allowing same-site attackers to force a victim administrator to rotate their recovery codes via a crafted URL. Exploit...

CVE-2026-45129

MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP Recovery Codes module does not validate requests correctly, allowing same-site attackers to rotate a victim administrator's recovery codes with a specially crafted URL. The Admin CP Home, Preferences, Recovery Codes...

EUVD-2026-61018

MyBB is free and open source forum software. Prior to 1.8.40, the Mod CP Report Center does not check permissions consistently, allowing moderators without report-management permission to mark reports as resolved. The modcp.php?action=doreports Mark Selected as Read handler is reachable with...

CVE-2026-45124

MyBB is free and open source forum software. Prior to 1.8.40, the Mod CP Report Center does not check permissions consistently, allowing moderators without report-management permission to mark reports as resolved. The modcp.php?action=doreports Mark Selected as Read handler is reachable with...

CVE-2026-45124 MyBB: Mod CP report resolution missing authorization

MyBB is free and open source forum software. Prior to 1.8.40, the Mod CP Report Center does not check permissions consistently, allowing moderators without report-management permission to mark reports as resolved. The modcp.php?action=doreports Mark Selected as Read handler is reachable with...

CVE-2026-45124

MyBB is free and open source forum software. Prior to 1.8.40, the Mod CP Report Center does not check permissions consistently, allowing moderators without report-management permission to mark reports as resolved. The modcp.php?action=doreports Mark Selected as Read handler is reachable with...

CVE-2026-45124 MyBB: Mod CP report resolution missing authorization

MyBB is free and open source forum software. Prior to 1.8.40, the Mod CP Report Center does not check permissions consistently, allowing moderators without report-management permission to mark reports as resolved. The modcp.php?action=doreports Mark Selected as Read handler is reachable with...

CVE-2026-45120 MyBB: Insufficient authorization for private calendar events

MyBB is free and open source forum software. Prior to 1.8.40, the calendar module does not verify private event status consistently, allowing users with viewing and moderation permissions to access and moderate private events. The private-event check used by getevents in inc/functionscalendar.php...

EUVD-2026-61017

MyBB is free and open source forum software. Prior to 1.8.40, the calendar module does not verify private event status consistently, allowing users with viewing and moderation permissions to access and moderate private events. The private-event check used by getevents in inc/functionscalendar.php...

CVE-2026-45120

MyBB is free and open source forum software. Prior to 1.8.40, the calendar module does not verify private event status consistently, allowing users with viewing and moderation permissions to access and moderate private events. The private-event check used by getevents in inc/functionscalendar.php...

CVE-2026-45120

MyBB is free and open source forum software. Prior to 1.8.40, the calendar module does not verify private event status consistently, allowing users with viewing and moderation permissions to access and moderate private events. The private-event check used by getevents in inc/functionscalendar.php...

EUVD-2026-61016

MyBB is free and open source forum software. Prior to 1.8.40, the User CP Buddy/Ignore List component does not validate reciprocal buddy-list updates correctly. The usercp.php?action=doeditlists delete handler removes the selected entry from the acting user's list and then updates...