PHP Group delivered release 5.2.6 to fix multiple security vulnerabilities.
The open source PHP Group outlined all of the changes and Secunia rated these vulnerabilities "moderately critical." Here's Secunia's breakdown of the vulnerabilities:
An unspecified error in the FastCGI SAPI can be exploited to cause a stack-based buffer overflow.
An unspecified error exists in processing incomplete multibyte characters within "escapeshellcmd()".
A security issue is caused due to an unspecified error. No further information is currently available.
An error in cURL can be exploited to bypass the "safe_mode" directive.
A boundary error in PCRE can potentially be exploited by malicious people to cause a DoS or compromise a vulnerable system.