Operation Rewrite: 2025 Chinese-Speaking Threat Actor Turns BadIIS Modules into Weaponized SEO Poisons
In March 2025, cybersecurity researchers uncovered Operation Rewrite, a large-scale search engine optimization (SEO) poisoning campaign attributed to a Chinese-speaking threat actor tracked as CL-UNK-1037, with links to Group 9 and DragonRank. Attackers compromised web and application servers, deploying malicious native IIS modules dubbed "BadIIS" to intercept, modify, and proxy web traffic. By injecting SEO content and redirecting legitimate visitors, the attackers increased rankings for illicit sites, harvested sensitive data, and exfiltrated web application source code. Multiple server types—web servers, domain controllers, and high-value hosts—were compromised, indicating substantial operational impact and risk to affected organizations and individuals.
Kill Chain