The Ruwiki Sleeper: How a Slumbering JavaScript Worm Paralyzed Wikipedia’s Global Infrastructure

During a security diagnostic, Wikimedia inadvertently executed a long-dormant, worm-like malicious JavaScript originating from the Russian Wikipedia that self-propagated and compromised numerous administrator accounts and modified Meta-Wiki content; the Foundation placed affected projects in read-only mode, removed the code, remediated the vulnerability, and found no evidence of user-data exfiltration.