wordpress – PwnDefend

How likely is successful mass exploitation of PHP2SHELL?

Never in a high alert scenario should be try and be too solid with our predictions, because this game is difficult! but given PHP2SHELL day is such a mad day, I’m going to break my typical model, however:

Personal view: this is a HIGH ALERT scenario but not an ACTIVE EXPLOITATION scenario (at the time of writing), so this is SERIOUS and requires paying attention to!

but the question, how likely is this to lead to mass exploitation? is there REAL tough and serious question we have to ask when considering the wider landscape of national security etc. so I’m going to at least explore it a bit!

Research

Using an LLM for assurance (WP2SHELL)

What better way to test than to eat ones own dogfood right! This site runs WordPress, it is fronted by Cloudflare, has wordfence and has automatic patching enabled (the default) in WordPress. So what better example to show that we can use an LLM + LLM created scripts to conduct assurance activities. This is mixing deterministic and non deterministic technologies to test and then assess.

Strategy

From TimThumb to wp2shell: 25 Years of WordPress Mass…

TL;DR: wp2shell (CVE-2026-63030 chained with CVE-2026-60137) matters because it is a core, pre-authentication RCE reachable on a stock, plugin-free install. That is the rare category. In 25 years, unauthenticated code execution against a bare WordPress install has happened only a handful of times. The overwhelming majority of WordPress mass compromise has ridden the plugin and theme supply chain and infrastructure abuse, not core. This post maps the history so you can see where wp2shell actually sits.

Threat Intel

WP2SHELL

Yesterday afternoon/early evening a patch for WordPress was released (7.0.2) which address two vulnerabilities which are named: WP2SHELL. This is a fast post (largely generated by Claude Opus) to provide some detail. For reference in our research we have found ~20% of WordPress sites still vulnerable as of a few hours ago (based on a sample), so this is a live scenario and it would be strongly advisable for organisations to take appropriate steps. This morning I’ve built a docker lab of a vulnerable WordPress site and demonstrated hash theft and web shell deployment to a vulnerable lab instance.

I’ve put some resources for people (use at own risk) into a repo: https://github.com/mr-r3b00t/wp2shell/

that includes a scanner, some info on the vulns and a PoC tool!

Guides

failed to open stream: Permission denied in /var/www/wordpress

I was doing some WordPress foo on the site (I know right, shockingly I don’t want to hand craft a website and I’d rather be helping customers or really anything else really) and I came into this error when I was installing the wpforms plugins:

 file_put_contents(/var/www/wordpress/wp-content/uploads/wpforms/cache/addons.json): failed to open stream: Permission denied in /var/www/wordpress/wp-content/plugins/wpforms-lite/src/Helpers/CacheBase.php on line 215

Defense

WordPress Security Considerations

WordPress is one of the most popular content management systems in the world today. I believe it is about 35% of the market share globally. That is a lot of sites.

I have been using WordPress for years myself; some people give it some stick for being vulnerable but that is usually them referring to third party plugins. I like it because you can build a site easily, without having to spend ages and you can deploy it and migrate etc. without having a huge headache. Read more “WordPress Security Considerations” →