These CVSS scores don't mean anything and it would be better for everyone if they stopped showing up in headlines. This is a somewhat situational Wordpress RCE that impacts only a couple themes.
Not sure if it’s a couple. Devs routinely make heavily edited copies of the core themes so there will be many, many unpublished themes that use the “page-“ prefix for templates; it was (is?) a reasonably common convention.
(No particular disagreement with the rest of your comment though)
This score specifically means that given some specific conditions, anyone can execute code over the network on a vulnerable WordPress setup. Is this not true?
I'm not saying that the vulnerability isn't severe or important to people running Wordpress, only that CVSS scores are literally a Ouija Board that can come out to whatever the user wants them to.
> CVSS scores are literally a Ouija Board that can come out to whatever the user wants them to.
Not really. They are very good at describing the technical impact. Sometimes pre-condition is very rare and that reduces overall likelihood but for those few it applies, the impact still could be catastrophic. Who wants to risk it if whole business could go down?
> This is a somewhat situational Wordpress RCE that impacts only a couple themes.
reply
That is dangerously incorrect, a whole lot of themes are vulnerable. The main pre-condition, "presence of a top-level directory named 'page-xxx' like 'page-templates' in the theme's directory" is actually an official recommendation in the WordPress documentation.
> As discussed in Organizing Theme Files, WordPress can recognize page templates stored in the theme’s root folder or in a first-level subdirectory of the theme folder. *The page-templates/ folder is a common convention* for organizing global page templates, but it is not required. Page templates can also be stored in other first-level subdirectories, such as templates/ or page_templates/.
Ironically, this 9 years old comment on the official documentation page of one of the affected functions perfectly describes both the nature and remediation of this major security flaw:
> Paul Ryan 9 years ago
> Note that locate_template() does not prevent directory traversal attacks, so if you’re passing a user-provided template name to the function, be sure to verify that it’s from one of the three appropriate locations (active theme directory, parent theme directory, or /wp-includes/theme-compat/ directory).
Ahahah I remember to have patched themes for clients by hand, years ago. A different time, where a core team would for whatever reason leave security holes around to be sure you need three frameworks around their pile of dung code.
pearcmd.php must exist, and register_argc_argv must be on, not common with hosting providers. But I am assuming the other themes and meeting conditions possibly affect a lot of WordPress sites.
As the article points out, one issue is that the official Docker container for PHP has this configuration.
However at least in principle all of the affected versions [0] could be automatically updated. Not sure if they have set it to auto-update as far back as 4.7 though.
[0] except 4.9.3 which has a bug in its automatic update mechanism.
pearcmd and register_argc_argv are just examples. get_page_template was unsanitized in some themes, that's the flaw, you could then combine it with one of a million unauthorized file upload in wordpress plugins to try and eval code. An attacker would like to use upload + this chain of requires (instead of just uploading a php) because of hardened configuration and the pwn can go unnoticed in the logs.
Also, with pearcmd (if you can get to that, there's no open_basedir) and containers a novice sysadmin will publish insecure sites.
(No particular disagreement with the rest of your comment though)
Not really. They are very good at describing the technical impact. Sometimes pre-condition is very rare and that reduces overall likelihood but for those few it applies, the impact still could be catastrophic. Who wants to risk it if whole business could go down?
That is dangerously incorrect, a whole lot of themes are vulnerable. The main pre-condition, "presence of a top-level directory named 'page-xxx' like 'page-templates' in the theme's directory" is actually an official recommendation in the WordPress documentation.
See here: https://developer.wordpress.org/themes/classic-themes/templa...
> As discussed in Organizing Theme Files, WordPress can recognize page templates stored in the theme’s root folder or in a first-level subdirectory of the theme folder. *The page-templates/ folder is a common convention* for organizing global page templates, but it is not required. Page templates can also be stored in other first-level subdirectories, such as templates/ or page_templates/.
> Paul Ryan 9 years ago
> Note that locate_template() does not prevent directory traversal attacks, so if you’re passing a user-provided template name to the function, be sure to verify that it’s from one of the three appropriate locations (active theme directory, parent theme directory, or /wp-includes/theme-compat/ directory).
https://developer.wordpress.org/reference/functions/locate_t...
However at least in principle all of the affected versions [0] could be automatically updated. Not sure if they have set it to auto-update as far back as 4.7 though.
[0] except 4.9.3 which has a bug in its automatic update mechanism.
Also, with pearcmd (if you can get to that, there's no open_basedir) and containers a novice sysadmin will publish insecure sites.