# MDTF – Meta Data and Taxonomies Filter <= 1.3.9 - Authenticated (Contributor+) Arbitrary Post Meta Update via Filter Data on Post Save

- **ID:** WPSEC-2026-0969
- **Plugin:** MDTF – Meta Data and Taxonomies Filter (`wp-meta-data-filter-and-taxonomy-filter`), https://wordpress.org/plugins/wp-meta-data-filter-and-taxonomy-filter/
- **Affected versions:** all versions before 1.4.0
- **Fixed in:** 1.4.0 (Update to 1.4.0 or later.)
- **Severity:** Medium 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N)
- **Weakness:** CWE-915
- **Usage among sites WPSec scans:** plugin Low, affected versions Low (as of 2026-10-14)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/wp-meta-data-filter-and-taxonomy-filter
- **Fix released:** 2026-10-13
- **Published:** 2026-10-14
- **URL:** https://wpsec.com/vuln/WPSEC-2026-0969/

## Description

The MDTF – Meta Data and Taxonomies Filter plugin for WordPress is vulnerable to arbitrary post meta modification via the 'page_meta_data_filter' post save data in all versions up to, and including, 1.3.9, due to the save_post handler writing every key of the submitted page_meta_data_filter array, with its unsanitized value, as post meta. The keys are not restricted to the plugin's own 'medafi_' prefix. This makes it possible for authenticated attackers, with Contributor-level access and above, to set arbitrary post meta, including protected underscore-prefixed keys, on posts they can edit.

## References

- https://wpsec.com/vuln/WPSEC-2026-0969/
- https://plugins.svn.wordpress.org/wp-meta-data-filter-and-taxonomy-filter/tags/1.4.0/
- https://wordpress.org/plugins/wp-meta-data-filter-and-taxonomy-filter/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-0969/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.