The attackers made a couple of mistakes that enabled the administrators at kernel.org to discover the breach and stop it before any major damage occurred. First, they used a known Linux rootkit called Phalanx that the admins were able to detect. And second, the attackers set up SSH backdoors on the compromised servers, which the admins also discovered. Had the hackers been specifically targeting the kernel.org servers, the attack probably would've looked quite different."
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