An outbreak of a worm on Tumblr, the microblogging platform, hit many accounts by taking advantage of the platform's reblogging capability. The payload of the worm was the publication of a posting angrily explaining how the worm's authors hated Tumblr users, was analysed by Sophos which noted that the malicious code was embedded mostly as a Base64-encoded string hidden within a data URI.
Once decoded and executed, it would pull code and content from another website.

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