vBulletin widgetConfig remote code execution vulnerability
unauthenticated, arbitrary remote code execution
vBulletin is the most popular web discussion forum platform by market share. 24 November an anonymous security researcher published proof-of-concept code highlighting this unauthenticated remote code execution vulnerability in vBulletin 5.x. Unauthenticated remote code execution is about as bad as software vulnerabilities get.
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