CVE-2026-4335
ShortPixel Image Optimizer <= 6.4.3 - Authenticated (Author+) Stored Cross-Site Scripting via Attachment Title
Description
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.
INFO
Published Date :
March 26, 2026, 4:17 a.m.
Last Modified :
March 26, 2026, 4:17 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-4335
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update the ShortPixel Image Optimizer plugin.
- Ensure plugin is version 6.5.0 or higher.
- Validate attachment titles are properly escaped.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-4335.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-4335 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-4335
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-4335 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-4335 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
Mar. 26, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N Added CWE CWE-79 Added Reference https://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.4.3/class/Controller/AjaxController.php#L449 Added Reference https://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.4.3/class/view/snippets/media-popup.php#L139 Added Reference https://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/trunk/class/Controller/AjaxController.php#L449 Added Reference https://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/trunk/class/view/snippets/media-popup.php#L139 Added Reference https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3490270%40shortpixel-image-optimiser&new=3490270%40shortpixel-image-optimiser&sfp_email=&sfph_mail= Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/a156234f-2644-4d17-aaa5-4f088cf48f73?source=cve