A new update to the WordPress open-source blogging and content management system (CMS) has been released that patches a pair of security vulnerabilities and includes 17 bug fixes that improve functionality.
One of the patched security vulnerabilities in Version 4.4.2 of WordPress was identified as a possible Server-Side Request Forgery (SSRF) vulnerability that can impact local addresses. The actual WordPress code commit that fixes the SSRF issue simply states that "0.1.2.3 is not a valid IP."
WordPress has patched SSRF vulnerabilities in the past, including one with the WordPress 3.5.2 release in June 2013. An SSRF is an interesting class of vulnerability in that it can help an attacker mask his or her actions. The Mitre Common Weakness Enumeration (CWE) classification for SSRF identifies that attack class as CWE-918.
"By providing URLs to unexpected hosts or ports, attackers can make it appear that the server is sending the request, possibly bypassing access controls such as firewalls that prevent the attackers from accessing the URLs directly," the Mitre CWE SSRF definition states.
The other vulnerability patched in the new WordPress release is identified as an open redirection attack. An open redirection attack is one that abuses Web functionality for linking to external sites.
"A web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a Redirect," Mitre's Open Redirect definition states. "This simplifies phishing attacks."
WordPress' fix for the open redirection is a new block of code that enforces better validation of the Web addresses used in HTTP redirects.
There is no indication at this point that attackers were exploiting either the SSRF or the open redirection flaw.
The WordPress 4.4.2 update is the second security update for WordPress so far in 2016, following the 4.4.1 update that debuted on Jan. 6. The WordPress 4.4.1 update provided a patch for a single cross-site scripting vulnerability as well as 52 bug fixes for WordPress features.
For many open-source WordPress users, both of the 2016 security updates have been automatically applied, thanks to WordPress' automatic patching capability for security updates that first debuted alongside the WordPress 3.8 release in December 2013.
Automatic patching is a security capability that can significantly reduce the risk exposure from potential vulnerabilities. In a talk at the Usenix Enigma conference last week, Rob Joyce, chief of the National Security Agency's Tailored Access Operations, applauded the increasing use of automated patching in software as a way to help protect users from attack.
Sean Michael Kerner is a senior editor at eWEEK and InternetNews.com. Follow him on Twitter @TechJournalist.