TITLE: PHP "curl_init()" Safe Mode Bypass Weakness

SECUNIA ADVISORY ID: SA20337

VERIFY ADVISORY: http://secunia.com/advisories/20337/

CRITICAL: Not critical

IMPACT: Security Bypass

WHERE: Local system

SOFTWARE:
PHP 5.1.x
http://secunia.com/product/6796/
PHP 4.4.x
http://secunia.com/product/5768/
PHP 5.0.x
http://secunia.com/product/3919/

DESCRIPTION: Maksymilian Arciemowicz has discovered a weakness in PHP, which can be exploited by malicious, local users to bypass certain security restrictions.

The weakness is caused due to an error in the handling of null byte characters in the "curl_init()" PHP function in the curl extension. This can be exploited to bypass the safe mode protection and access other users' files located in the same directory as the running script.

Successful exploitation requires that the curl extension is installed and enabled.

The weakness has been confirmed in versions 5.0.5 and 5.1.4, and has also been reported in version 4.4.2. Other versions may also be affected.

SOLUTION: The weakness has been fixed in the CVS repository.

Do not rely on the safe mode protection for files located in the same directory as untrusted scripts.

PROVIDED AND/OR DISCOVERED BY: Maksymilian Arciemowicz

ORIGINAL ADVISORY: http://securityreason.com/achievement_securityalert/39