University subdomains keep surfacing in porn searches because admins never purge unused DNS records. When a department abandons a subdomain, its CNAME points to a third‑party host that can be hijacked. Search engines then rank the rogue domain, sending visitors straight to adult content online traffic.

The root cause is simple: CNAMEs have no expiry, and university IT teams rarely track them. Decentralized campuses let labs and clubs create subdomains without a central inventory. When staff leave, no decommissioning process removes the dangling records which causes unwanted traffic to be redirected.

Spotting hijacked sites is simple: query Google with site:university.edu "porn" or "xxx" and review the hits. Many returned domains still redirect to adult sites, and even when the target shuts down, the CNAME lingers, keeping the URL indexed for students and faculty who search academic.

Universities must maintain a live subdomain inventory and audit CNAMEs regularly. Removing inactive records stops hijacking, but even after cleanup, Google may keep the URL in search results. So far, only a handful of schools have purged dangling CNAMEs, and most still face visibility issues.