CVE-2026-48944
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk21th percentile - higher than 21% of all known CVEs
Summary
A vulnerability in the K2 component for Joomla! allows an Author to copy any file readable by the web user (e.g., configuration.php or /etc/passwd) to the /media/k2/attachments/ directory by manipulating the `attachment[N][existing]` POST field. Lack of source path validation and `..` filtering in `JPath::clean` enables a path traversal attack.
Risk Assessment
An attacker with Author privileges can access sensitive server files, including Joomla! configuration files (containing database credentials) or system files, leading to full site compromise and potentially server takeover.
Recommendation
Immediately update the K2 component to the latest patched version. As a temporary workaround, disable the K2 attachment upload feature or apply WAF rules to block manipulation of the `existing` field.
Other vulnerabilities in K2
See all- CVE-2026-48946Medium
A vulnerability in the K2 component allows authors to upload PHP files as article attachments. Apache executes these files, enabling remote PHP code execution in the web server context.
- CVE-2026-48945Medium
A vulnerability in the K2 component for Joomla! allows uploading a ZIP/TAR archive containing PHP files to the gallery directory. The system only renames image files, leaving non-image files (including PHP) extracted as-is and accessible via HTTP, enabling remote code execution.
- CVE-2026-48943Medium
A mass-assignment vulnerability in K2 ≤ 2.24 exists in the `plg_user_k2` system user plugin. A registered Joomla user can, by including the `K2UserForm=1` field in a standard `com_users` `profile.save` POST request, write arbitrary values into the `notes`, `image`, and `plugins` columns of their own row in the `#__k2_users` table, which are not exposed by the K2 frontend profile-edit form.
- CVE-2026-48942Medium
K2 version 2.26 and earlier renders the `#__k2_users.image` column directly into HTML `src` attributes via two distinct templates, in both cases without HTML escaping.
- CVE-2026-48941Medium
A vulnerability in the K2 component for Joomla! allows an unauthenticated attacker to delete arbitrary directories via the `sigProFolder` parameter in the `item.checkin` task. The attacker can exploit this flaw to remove gallery directories under `/media/k2/galleries/`.
- CVE-2026-48940Low
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.
Original NVD description (English source)
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 therefore copy `configuration.php` (or any other file readable by the web user — including `../../../etc/passwd`) into `/media/k2/attachments/`, then retrieve the contents via the K2 attachment-download endpoint.