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

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.

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.