The default soap.wsdl_cache_dir setting in (1) php.ini-production and (2) php.ini-development in PHP through 5.6.7 specifies the /tmp directory, which makes it easier for local users to conduct WSDL injection attacks by creating a file under /tmp with a predictable filename that is used by the get_sdl function in ext/soap/php_sdl.c.

References

• https://nvd.nist.gov/vuln/detail/CVE-2013-6501
• https://bugzilla.redhat.com/show_bug.cgi?id=1009103
• https://security.gentoo.org/glsa/201606-10
• http://lists.opensuse.org/opensuse-security-announce/2015-03/msg00003.html
• http://www.oracle.com/technetwork/topics/security/bulletinjul2015-2511963.html
• http://www.securityfocus.com/bid/72530