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Keywords: Tumblr, compromise, passwords, email addresses
DBSA ID: 2016-05301
Regarding: Tumblr Compromise
Date: 2016 05 30
Last Modified: 20160530170342 by Kradorex Xeron
Who should take note: All Tumblr Users
Rationale: Users need to ensure their information is secured.
Rationale: Usernames, salted+hashed passwords, email addresses among other information has reportedly been compromised.
Spread of Issue: SINGLE-PLATFORM HIGH
Rationale: 65 Million records are reported to have been compromised.
Tumblr is a social networking site targetted toward sharing various kinds of content between users. On 30 May 2016, it has been reported that in 2013 that there was a compromise of Tumblr's systems resulting in 65 million email addresses and passwords being compromised. Tumblr has reported that the passwords were stored in a hashed and salted manner, a technique that resists rainbow table attacks where a dictionary of suspected hashed passwords are compared to the database without requiring brute force techniques.
Users should change their Tumblr passwords on a rolling basis to temporary passwords, once immediately and then again after 2 weeks users may reset to a more longterm password. This method ensures that the service has fixed the vulnerability before one becomes too reliant upon a new password. Users should also ensure that their password is not shared among other sites, to which those passwords that do will also need to be reset in a single change.
Users should also be highly suspicious of any contacts via email and use non-email methods to verify legitimacy of such email. Password resets should only be performed through known good links.