# Import and export users and customers <= 2.5.8 - Authenticated (Subscriber+) Privilege Escalation via CSV Export Cell Injection

- **ID:** WPSEC-2026-1626
- **Plugin:** Import and export users and customers (`import-users-from-csv-with-meta`), https://wordpress.org/plugins/import-users-from-csv-with-meta/
- **Affected versions:** all versions before 2.5.9
- **Fixed in:** 2.5.9 (Update to 2.5.9 or later.)
- **Severity:** High 7.1 (CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H)
- **Weakness:** CWE-269
- **Usage among sites WPSec scans:** plugin Low, affected versions Low (as of 2026-10-25)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/import-users-from-csv-with-meta
- **Fix released:** 2026-10-23
- **Published:** 2026-10-24
- **URL:** https://wpsec.com/vuln/WPSEC-2026-1626/

## Description

The Import and export users and customers plugin for WordPress is vulnerable to Privilege Escalation via the user export and re-import workflow in all versions up to, and including, 2.5.8, due to the exporter writing CSV cells, and the importer reading them, with a NUL byte as the escape character without removing NUL bytes from exported values. A NUL byte placed before a quote stops fputcsv() from doubling that quote, while fgetcsv() reads the same bytes differently, so the cell boundaries shift and the rest of a profile value is parsed as extra columns and rows. This makes it possible for authenticated attackers, with subscriber-level access and above, to store crafted profile values that inject arbitrary user rows into the export, such as their own username with the administrator role, which are applied when a user with import and export permissions exports the users and imports the generated CSV again with role updates enabled.

## References

- https://wpsec.com/vuln/WPSEC-2026-1626/
- https://plugins.svn.wordpress.org/import-users-from-csv-with-meta/tags/2.5.9/
- https://wordpress.org/plugins/import-users-from-csv-with-meta/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-1626/

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.