Ubuntu Forums’ database was recently discovered hacked after Canonical, the company behind Ubuntu, was alerted that someone claimed to have a copy of the Forums database. An investigation revealed that a security breach had exposed usernames, email, and IP addresses for 2 million users. Passwords, however, were not accessed.
Canonical explained in a blog: "No active passwords were accessed; the passwords stored in this table were random strings as the Ubuntu Forums rely on Ubuntu Single Sign On for logins. The attacker did download these random strings (which were hashed and salted)."
The company further explained that the breach was due to a SQL injection vulnerability in the platform which powers the forum and which had not been patched.
“The attacker had the ability to inject certain formatted SQL to the Forums database on the Forums database servers…. This gave them the ability to read from any table, but we believe they only ever read from the ‘user’ table,” says Canonical.
The website was shut down as a precautionary measure and the server wiped clean and rebuilt.
Read more details here.