The provider of free antivirus software took its message board offline after the breach.
“This forum for many years has been hosted on a third-party software platform and how the attacker breached the forum is not yet known,” Avast CEO Vince Steckler wrote in a blog post on 5/26. “We do believe that the attack just occurred and we detected it essentially immediately.”
User nicknames, user names, email addresses and hashed (one-way encrypted) passwords were compromised.
While the passwords were hashed, it could be possible for a sophisticated thief to discern many of the passwords, Steckler acknowledged.
No payment, license, or financial systems or other data was accessed, he said.
Less than 0.2 percent of Avast’s 200 million users were affected.
Avast was using Simple Machines’ Forum to power its message board, Graham Cluley reports. “It’s natural to suspect that the anti-virus firm had not kept the forum software properly up-to-date with the latest security patches,” he said.
ThreatWatch is a regularly updated catalog of data breaches successfully striking every sector of the globe, as reported by journalists, researchers and the victims themselves.