CVE-2026-4335 (GCVE-0-2026-4335)

Vulnerability from cvelistv5 – Published: 2026-03-26 02:25 – Updated: 2026-04-08 17:12
VLAI?
Title
ShortPixel Image Optimizer <= 6.4.3 - Authenticated (Author+) Stored Cross-Site Scripting via Attachment Title
Summary
The ShortPixel Image Optimizer plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the attachment post_title in all versions up to, and including, 6.4.3. This is due to insufficient output escaping in the getEditorPopup() function and its corresponding media-popup.php template. Specifically, the attachment's post_title is retrieved from the database via get_post() in AjaxController.php (line 435) and passed directly to the view template (line 449), where it is rendered into an HTML input element's value attribute without esc_attr() escaping (media-popup.php line 139). Since WordPress allows Authors to set arbitrary attachment titles (including double-quote characters) via the REST API, a malicious author can craft an attachment title that breaks out of the HTML attribute and injects arbitrary JavaScript event handlers. This makes it possible for authenticated attackers, with Author-level access and above, to inject arbitrary web scripts that execute whenever a higher-privileged user (such as an administrator) opens the ShortPixel AI editor popup (Background Removal or Image Upscale) for the poisoned attachment.
Severity ?
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
shortpixel ShortPixel Image Optimizer – Optimize Images, Convert WebP & AVIF Affected: 0 , ≤ 6.4.3 (semver)
Create a notification for this product.
Credits
daroo
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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