Getk2 ≫ K2

The K2 article gallery upload path accepts a zip/tar archive, extracts it under `/media/k2/galleries/<id>/`, and only renames image files (gif/jpg/jpeg/png/webp) to safe names — non-image files (including `.php`) are extracted as-is and remain execut...

A Joomla user with K2 "create item" rights (Author tier by default) can submit an article whose `embedVideo` POST field contains a raw `<script>` tag; K2 stores it verbatim and renders it unescaped to any visitor of the article page.

The K2 frontend `item.checkin` task accepts an unauthenticated `sigProFolder` query parameter and uses it directly to address a `JFolder::delete()` call under `/media/k2/galleries/`

The K2 frontend article-attachment upload path accepts files whose extension is `.php`, and Apache's standard mod_php matches `\.php$` and executes them under the K2 web user. A K2 Author can upload a `shell.php`, then fetch `/media/k2/attachments/sh...

The K2 frontend article-save handler accepts an `attachment[N][existing]` POST field that is concatenated with `JPATH_SITE/` and passed to `JFile::copy()`. `JPath::clean` does NOT strip `..`, and there is no allow-list of source paths. An Author can ...

K2 ≤ 2.26 renders the `#__k2_users.image` column directly into HTML `src` attributes via two distinct templates, in both cases without HTML escaping.

K2 ≤ 2.24 contains a mass-assignment defect in the K2 system user plugin `plg_user_k2`. A Registered Joomla user, by including the field `K2UserForm=1` in a standard `com_users` `profile.save` POST, can write arbitrary values into the `notes`, `image...