If one user sees a defaced website while another does not, what is the most likely cause?

• A. DNS cache poisoning
• B. Caching issue or internal network configuration
• C. TLS misconfiguration
• D. Browser cache issue

Answer: (B)

When results differ between users, it points to something in the path to the site being cached or misconfigured rather than the site itself. A browser cache, a DNS resolver cache, or an HTTP proxy cache can serve a stale or altered version of the page to one user while another user fetches the fresh content from the real server. Internal network configurations, such as split-horizon DNS or proxy settings, can route different users to different servers or caches, producing a defaced page for one person but not another. This explains the discrepancy more plausibly than a site-wide issue. DNS cache poisoning would likely affect many users on the same resolver, TLS misconfiguration would lead to certificate warnings, and while a browser cache issue is possible, the broader caching or network configuration explanation covers the observed behavior more comprehensively.