The developers of the vBulletin forum software have taken down their official website and forum following a hacker attack that may have resulted in user data getting stolen.
Users who attempted to access the vBulletin forum on Sunday were greeted by a message that read “Hacked by Coldzer0.” The website and forum currently display a “down for maintenance” message.
The extent of the damage is unclear, but the hacker has published screenshots apparently showing that he managed to upload a shell to the vBulletin website and obtain user data, including user IDs, names, email addresses, security questions and answers, and password salts, DataBreaches.net reported.
Internet Brands-owned vBulletin Solutions has yet to release a statement on the incident and the company could not immediately be reached for comment.
Users should change their passwords as a precaution as soon as the website comes back online. If the same password is used on other websites, it should be changed there as well.
The attacker claims to have used a zero-day vulnerability in vBulletin to hack this and other websites powered by the popular forum software.
DataBreaches.net has connected the online moniker “Coldzer0” to Mohamed Osama, a malware analyst and security researcher based in Egypt. Osama has removed all references to the vBulletin attack from his social media accounts, and deleted the content of his personal website after his name was linked to the breach.
Vulnerabilities in unpatched versions of vBulletin are often leveraged to breach websites using the forum software. In 2013, thousands of websites were hacked via a security hole in vBulletin.
Australian security expert Troy Hunt, owner of the Have I Been Pwned service, which allows users to learn if and where their personal data has been compromised, noted that Have I Been Pwned includes data leaked as a result of several vBulletin-powered website breaches.
I’ve commented before on how frequently vBulletin gets hacked, but I didn’t mean their actual site as well! https://t.co/StV1hR8PIS
— Troy Hunt (@troyhunt) October 31, 2015
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