PHP Session Hijacking
Can users alter their session identifiers?
In PHP, sessions are identified by a unique ID. This ID is generally stored in a cookie named "PHPSESSID" and is passed to the server with each request. However, users can potentially modify this cookie, thereby changing their session ID.
Server-side vs. Client-side Sessions
It's essential to differentiate between server-side and client-side sessions. Server-side sessions are managed by the server and store data on the server itself. Client-side sessions, on the other hand, are handled by the browser and involve features like browser histories and tabbed browsing.
Contents vs. Identifier Change
While users cannot modify the contents of a server-side session (stored on the server), they can potentially change the session identifier. This is because the identifier is typically passed via a cookie, which users can alter.
Protection Measures
To safeguard against session hijacking, implement additional measures to identify users beyond session identifiers. This could include user agents, IP addresses, or other cookies. Additionally, using HTTPS with the "httponly" flag set to true can help secure session cookies against theft.
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