# CVE-2026-77365: Optimole Stored Cross-Site Scripting in image optimization parameter

Source: https://junglewise.ai/threats/cve-2026-77365-optimole-stored-cross-site-scripting-in-image-optimization  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-28. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-77365 · Severity: high · CVSS 7.2 · Published 2026-08-28

Optimole is a WordPress plugin that optimizes and delivers images efficiently. An unauthenticated attacker can inject malicious JavaScript code that persists in the website and executes in the browsers of all visitors, potentially compromising user accounts, stealing credentials, or defacing the website.

Vendors: [Optimole](https://junglewise.ai/threats/vendors/optimole).

## Quick answers

**Is CVE-2026-77365 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-77365 being exploited in the wild.

**How severe is CVE-2026-77365?** High severity, with a CVSS score of 7.2, published 28 August 2026.

**Which products and versions are affected?** Optimole – Optimize Images up to and including 4.2.10.

**Is there a fix for CVE-2026-77365?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-77365 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-77365?** Check whether you run Optimole – Optimize Images at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a Stored Cross-Site Scripting (XSS) flaw in the Optimole WordPress plugin affecting versions up to 4.2.10. The 'a' parameter (above_fold_images) in the REST API endpoint fails to properly sanitize and escape user input, allowing unauthenticated attackers to inject arbitrary JavaScript. The injected payload is stored in the database and executed in the browsers of all users who access affected pages. No authentication is required to exploit this vulnerability, and successful exploitation can lead to session hijacking, credential theft, or malware distribution to website visitors.

## Affected products

- Optimole Optimole – Optimize Images up to and including 4.2.10

## Timeline

- 2026-08-28: disclosed

## References

- [https://plugins.trac.wordpress.org/browser/optimole-wp/tags/4.2.10/inc/manager.php](https://plugins.trac.wordpress.org/browser/optimole-wp/tags/4.2.10/inc/manager.php)
- [https://plugins.trac.wordpress.org/browser/optimole-wp/tags/4.2.10/inc/rest.php](https://plugins.trac.wordpress.org/browser/optimole-wp/tags/4.2.10/inc/rest.php)

## Related threats

- [Optimole stored cross-site scripting in image optimization plugin](https://junglewise.ai/threats/cve-2026-120739-the-optimole-optimize-images-convert-webp-avif-cdn-lazy-load)