# Smush – Lazy Load Images, Optimize & Compress Images <= 4.3.5 - Authenticated (Author+) Insecure Direct Object Reference to Arbitrary Attachment Optimization, Restoration and Ignore Status Modification

- **ID:** WPSEC-2026-2386
- **Plugin:** Smush – Image Optimization, Compression, Lazy Load, WebP & CDN (`wp-smushit`), https://wordpress.org/plugins/wp-smushit/
- **Affected versions:** all versions before 4.3.6
- **Fixed in:** 4.3.6 (Update to 4.3.6 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-639
- **Usage among sites WPSec scans:** plugin High, affected versions High (as of 2026-11-03)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/wp-smushit
- **Fix released:** 2026-11-02
- **Published:** 2026-11-03
- **URL:** https://wpsec.com/vuln/WPSEC-2026-2386/

## Description

The Smush plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 4.3.5 due to missing per-attachment authorization checks in the AJAX single image optimization, backup restore and ignore/unignore handlers and in the media library bulk restore action, which only verified the generic 'upload_files' capability. This makes it possible for authenticated attackers, with Author-level access and above, to optimize, restore original backups of, or change the ignored status of attachments belonging to other users that they are not allowed to edit.

## References

- https://wpsec.com/vuln/WPSEC-2026-2386/
- https://plugins.svn.wordpress.org/wp-smushit/tags/4.3.6/
- https://wordpress.org/plugins/wp-smushit/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-2386/

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.