The Modern Threat Landscape

Man-in-the-middle attacks represent one of the most pervasive threats that HTTPS protects against. These attacks occur when malicious actors position themselves between users and websites, intercepting and potentially modifying communications. On unencrypted HTTP connections, attackers can read passwords, steal session cookies, inject malicious code, or redirect users to phishing sites. Public Wi-Fi networks particularly facilitate these attacks, as attackers can easily join the same network as victims and intercept their traffic.

Content injection attacks have become increasingly sophisticated and widespread. Internet Service Providers have been caught injecting advertisements into HTTP pages to generate revenue. Malicious actors inject cryptocurrency mining scripts, turning visitors' computers into mining resources without consent. Government censorship apparatus modifies content to control information flow. Hotels and airports inject promotional content into browsing sessions. HTTPS prevents all these injections by ensuring content integrity from server to browser.

Session hijacking and cookie theft pose serious risks on HTTP connections. Attackers can steal session cookies transmitted in plain text, gaining unauthorized access to user accounts without knowing passwords. This vulnerability affects not just the login process but entire browsing sessions. Social media accounts, email access, and administrative privileges become vulnerable when session cookies travel unencrypted. Even sites that use HTTPS for login but HTTP for subsequent pages expose users to session hijacking.

Data harvesting and profiling threaten user privacy on unprecedented scales. Without HTTPS, network observers can build detailed profiles of user behavior, interests, and activities. This information becomes valuable for targeted advertising, price discrimination, or more nefarious purposes like blackmail or persecution. The aggregation of seemingly innocent browsing data can reveal sensitive information about health conditions, political views, financial status, or personal relationships.