Bug #38104 [Wfx->Csd]: session_start()/session_write_close() creates multiple session cookies headers

Edit report at https://bugs.php.net/bug.php?id=38104&edit=1 ID: 38104 Updated by: yohgaki@php.net Reported by: m dot v dot veluw dot smscity at gmail dot com Summary: session_start()/session_write_close() creates multiple session cookies headers -Status: Wont fix +Status: Closed Type: Bug Package: Session related Operating System: any PHP Version: 5.1.4 Assigned To: yohgaki Block user comment: N Private report: N New Comment: Time goes by. I fixed this already. If you have problem, please open new bug report. Previous Comments: ------------------------------------------------------------------------ [2015-08-10 20:18:18] waldoc at latinmail dot com A LOT of people is using session_start(); and session_write_close(); as a way to update $_SESSION data and make it available for other scripts (usually called using AJAX) The problem is session_start(); and his SEND HEADERS AGAIN Feature. So the solution is simple: Add a new function called session_write_open(); in order to be used with session_write_close(); Headers are only set by session_start(), and session_write_open() will resume that session without sending headers again. If that solution is too complicated, then add a new option to the session_start(); ie: session_start(MUTE_HEADERS) that restore the session without send headers again. I'm pretty sure that the second implementation is even more easy and fast to implement, because if MUTE_HEADERS are set, then you got to skip the send header part of the function. Hope this features will be present in the next release. Best regards ------------------------------------------------------------------------ [2015-02-02 17:09:53] yohgaki@php.net If only one header is sent, multiple sessions cannot be used. Therefore, it will not be fixed. ------------------------------------------------------------------------ [2014-09-10 10:29:27] yohgaki@php.net I don't remember well, but I think I've dealt "multiple cookies" issue partially. I might not for this case. I'll fix it sends multiple cookies, please let us know. Unfortunately, PHP does not make sure that old session is not deleted. If old session was authenticated before session regeneration, bad luck. (We could still say "it's users fault", though) To remove old session, it must be deleted asynchronous manner. However, few people against this change and insist synchronous deletion which cannot be done. (i.e. Web server and client is _not_ synchronized, thus synchronous deletion can cause serious problem) Anyway, please update PHP version if there is issue. If not, please close this again. Thank you. ------------------------------------------------------------------------ [2014-09-10 05:59:42] bgardner at noggin dot com dot au The following highlights the bug <?php session_start(); $old_id = session_id(); session_regenerate_id(); $new_id = session_id(); session_write_close(); ?> <html> <head> <title>Session test</title> </head> <body> <p>Old id : <?php print $old_id ?> <p>New id : <?php print $new_id ?> </body> </html> If you hit this page on a domain you have not previously visited, it will send two Set-Cookie headers for the session id This is a common scenario when logging in to prevent session fixation attacks https://www.owasp.org/index.php/Session_fixation This is not a problem if the user does 1. Login screen - display form controls to login 2. Submit credentials to login page - session regenerated However, if they directly submit their credentials without first visiting the domain, then it does occur ------------------------------------------------------------------------ [2013-05-29 02:47:34] jonathan at doubledotmedia dot com I am encountering the same issue at the moment on a codebase I am working on; the issue we are seeing is that we make many simultaneous AJAX requests, but they block each other because only one can hold the session open at a time. We are currently working around it by using multiple session_start() and session_write_close() functions, but this is sending multiple (identical) Set- Cookie headers to the client, which is incorrect. Either session_start needs to not send duplicate headers, or we need a session_reopen() function ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=38104 -- Edit this bug report at https://bugs.php.net/bug.php?id=38104&edit=1