A bug in PHP 5 was released, somewhat accidentally (apparently somebody made a reddit post public inadvertently…why people would use these sites for sensitive info is beyond me…anyhoo), and is finally patched by RedHat and derivatives, CentOS, ScientificLinux –
Ubuntu has also released a patch –
RHEL5&6 would be no longer vulerable to either CVE-2012-1823 or its re-incarnation CVE-2012-2311, as the bug was not correctly patched the first time around. RedHat claims their fix is complete, I cannot vouch for Ubuntu so don’t blame me if you have to patch it again later.
The vulnerability itself was quite old, sneaking into the code 8 years ago and lying undiscovered until recently. It relies on the use of php-cgi (running PHP as a cgi forked process, not in the more mainstream mod_php mechanism). One of the many consequences of this bug was source code exposure (via ?-s), and many PHP sites having database username/password information contained in the PHP code, this vulnerability could and will compromise sites where this is the case that remain unpatched. This is one of the many reasons it is a better idea to use PHP include functionality to provide database/user/password/security connnection info to PHP, and have that included file outside of the http webroot in the first place. Other possible exploits would be to execute code/upload files on the remote filesystem….scary, nasty stuff!!!!
Even the allmighty Facebook, set for an IPO this week, was vulnerable to this (they were running as a cgi, apparently!!)
The IPO could have been something of a bust had Facebook been hacked a week before it hopes to raise 95$ billion USD. Who would have seen that one coming?!?!?!?!