CVE-2014-8626: Buffer Overflow

While investigating the CVE-2014-3668 issue (bug 1154503), it was discovered that older PHP versions are affected by another issue in the ISO8601 date format parsing code. The internal datefromISO8601() function failed to check buffer boundary when copying input string to a local fixed sized buffer.

http://git.php.net/?p=php-src.git;a=blob;f=ext/xmlrpc/libxmlrpc/xmlrpc.c;h=d82f270#l164

This leads to a stack based buffer overflow. A PHP application that uses the PHP xmlrpc extension (in Red Hat Enterprise Linux and Fedora, this extension is available via separate php-xmlrpc package) to implement an XML-RPC server (or client) could crash or, possibly, execute arbitrary code while parsing a specially crafted XML-RPC request.

This problem was fixed upstream in PHP version 5.2.7 via:

http://git.php.net/?p=php-src.git;a=commitdiff;h=c818d0d https://bugs.php.net/bug.php?id=45226

The actual impact of the fix was apparently not realized upstream, as the fix was only listed as a bug fix, rather than security fix, in the upstream ChangeLog:

http://php.net/ChangeLog-5.php#5.2.7

Fixed bugs #45226, #18916 (xmlrpcsettype() segfaults and wrong behavior with valid ISO8601 date string). (Jeff Lawsons)

Impact of this issue is mitigated on Red Hat Enterprise Linux 5, where php packages are built with the Stack Protector protection, which lead to early detection of the overflow, leading to application abort before the overwritten saved instruction pointer is used. The php packages in Red Hat Enterprise Linux 4 are not built with the Stack Protector protection to mitigate the code execution impact.

The php packages in Red Hat Enterprise Linux 6 and later, as well as php53 packages in Red Hat Enterprise Linux 5 are based on the fixed upstream version and were not affected by this issue.

— Red Hat