WordPress: Unauthenticated path traversal leading to conditional RCE

Edit: wow that's a lot of downvotes! I'm surprised people can't identify a trivial reasoning failure.

Probably true, but for whatever reason Wordpress seems to attract an awful lot of people that do not know what they are doing

People who _don't_ know what they are doing are using WP for every project, that they touch, because it is all they know. Given WPs database design, the assumptions baked into that, and the complications resulting from that, make anything other than a posts and pages website a PITA.

This in turn requires one to install shitty plugins, or spend time developing a minimalistic solution to each new challenge. With every plugin the attack surface grows, and the vast majority of larger WP sites is this cobbled together mess of WP plugins, having some WP expert trying to make them all work together without stepping on each other's toes, while hopelessly falling behind on updates, because updates could, and _will_ break things.

People only knowing PHP and WP, try to use WP as a sledgehammer, not realizing that hammer actually being made out of glass. Very few plugins are actually minimalistic, no-bloat, safe, well-developed. Lots of those plugins are 80% marketing fluff and wanting to make a business out of worse than mediocre code bases. That's also due to many people in that community being exactly those, who don't know anything but WP.

Even normal core WP updates can break the legality of ones site. I have had that at some point, where after some WP update it started loading emojis from a friggin third party, to replace the unicode symbol I had used. I was furious, because this needs to be part of the data protection policies/statements. One does not simply load a third party shit, replacing what the dev actually put there, which was just a unicode symbol. That's an idiotic thing to do. If I wanted third-party emojis, I would have included them myself.

Finally, some big pages run on WP says not much, given the catastrophic state of many websites. whitehouse.gov is laughably badly made. Another complete failure. The first thing I see that it loads Google tags manager. A government site loading shit.

    fonts.googleapis.com
    googletagmanager.com
    gstatic.com
    parsely.com

And the navigation font is tiiiny. What a horrendous design.

When I click on some navigation link, it wants to go to:

    https://www.whitehouse.gov/wp-content/uploads/2026/01/Wide_Site_Primary_02.mp4

If it is a prime example, then it is a prime example of a very shitty made website, by people, who don't know what they should be doing.

So all this shows is one can make a shitty site using WP. Great. I am sure one can also make a not shitty site using WP. Like you say, _"If you know what you are doing ..."_. Just that most WP people don't. They don't know how to not make a mess, or choose the short-term easy way out, and install tons of shitty plugins. Many of them just have to put things up once initially and are paid, or hold the hand open for some maintenance fee they extract, required only due to how badly made these WP sites are.

If you know what you're doing, a loaded gun without a safety is fine, too. But you have the option, why not pick the unloaded one with a safety mechanism?

For the Wordpress RCE (nominally CVSS 9.2), it looks like many standard deployments of WordPress would be affected, barring extra mitigations. But in the case of these Hugo ones (9.3), it looks like very specific circumstances (anti-mitigations, if you will) are needed. E.g. running arbitrary builds of untrusted user content without a sandbox; running it in a GitHub workflow against PRs from untrusted contributors, etc.

On a fresh WP install, a random user can't upload PHP files. Normally you don't even need to allow random users to register an account since avatars on comments come from gravatar anyway.