Description
WordPress Plugin Gravity Forms is prone to a vulnerability that lets attackers upload arbitrary files because the application fails to properly sanitize user-supplied input. An attacker can exploit this vulnerability to upload arbitrary code and run it in the context of the webserver process. This may facilitate unauthorized access or privilege escalation; other attacks are also possible. WordPress Plugin Gravity Forms version 1.8.19 is vulnerable; prior versions may also be affected.
Remediation
Update to plugin version 1.8.20 or latest
References
https://blog.sucuri.net/2015/02/malware-cleanup-to-arbitrary-file-upload-in-gravity-forms.html
https://www.exploit-db.com/exploits/39969/
https://packetstormsecurity.com/files/137522/WordPress-Gravity-Forms-1.8.19-Shell-Upload.html
Related Vulnerabilities
WordPress Plugin Like Button Rating-LikeBtn Security Bypass (2.5.3)
WordPress Plugin Easy Image Gallery Cross-Site Scripting (1.1.1)
MediaWiki Permissions, Privileges, and Access Controls Vulnerability (CVE-2015-8004)
WordPress Plugin Helpful Information Disclosure (4.5.25)
Joomla Permissions, Privileges, and Access Controls Vulnerability (CVE-2006-4475)