EUVD-2026-13838
GHSA-jph4-mv6f-wg9x
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Output encoding, context-aware escaping
MITRE ATT&CK
2 techniques across 2 tactics: Initial Access, Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | The CVSS 3.1 score of 6.4 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N) reflects medium severity with network accessibility, low attack complexity, and low privilege requirements, but the impact is scoped to confidentiality and integrity (no availability impact). The attack requires authenticated access at Contributor level or above, which substantially reduces the risk profile compared to unauthenticated XSS vulnerabilities. However, the UI:N (no user interaction required) factor increases practical risk once injected. The presence of a patched commit in the official GitHub repository and the detailed vulnerability disclosure via Wordfence indicate this is a mature, well-documented issue with available remediation. Real-world risk is moderate: the barrier to exploitation is authentication plus feature enablement, but the payload persists and affects all site visitors, making it suitable for targeted attacks against high-value WordPress installations rather than mass exploitation. |
| Exploit ScenarioDerived | A malicious Contributor-level user (e.g., a compromised or disgruntled guest author) accesses the WordPress post editor, injects a JavaScript payload into the 'ao_post_preload' meta field using the Autoptimize metabox interface, and saves the post. When any site visitor (including administrators) views the post and the Image optimization or Lazy-load images plugin feature is active, the unescaped payload executes in their browser, allowing cookie theft, admin account hijacking, or redirection to malware sites. A proof-of-concept payload structure is evident in the referenced source code locations (autoptimizeMetabox.php line 276 and autoptimizeImages.php lines 804/938), where meta retrieval and HTML rendering occur without sanitization or escaping. |
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Alert meAnalysisAIv1 – Mar 20, 2026
A Stored Cross-Site Scripting (XSS) vulnerability exists in the Autoptimize WordPress plugin through version 3.1.14, caused by insufficient input sanitization in the ao_metabox_save() function and missing output escaping when rendering the 'ao_post_preload' meta value into HTML link tags. Authenticated attackers with Contributor-level access or higher can inject arbitrary JavaScript that executes whenever users access pages with the Image optimization or Lazy-load images settings enabled, potentially affecting all users of compromised sites. The vulnerability has been patched and proof-of-concept code is available in the referenced GitHub commit.
RemediationAI
Immediately upgrade Autoptimize to a patched version released after 3.1.14; consult the plugin's official WordPress repository and GitHub project for the latest stable release. As a temporary mitigation pending patching, administrators should disable the Image optimization and Lazy-load images settings within the Autoptimize configuration to prevent payload execution, and restrict post editing capabilities to trusted administrative accounts only, reducing the attack surface from Contributor-level accounts. Monitor post revisions and meta values for suspicious preload directives, and consider using WordPress security plugins with XSS detection to alert on anomalous link injections in post meta data.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
The Autoptimize plugin (CPE: cpe:2.3:a:optimizingmatters:autoptimize:*:*:*:*:*:*:*:*) is a WordPress optimization plugin that handles image optimization and lazy-loading. The vulnerability stems from a CWE-79 (Improper Neutralization of Input During Web Page Generation) defect affecting PHP code. Specifically, the ao_metabox_save() function in autoptimizeMetabox.php (line 276) fails to sanitize the 'ao_post_preload' post meta value during input handling, and the rendering code in autoptimizeImages.php (lines 804 and 938) fails to properly escape this value when constructing HTML link elements. This allows attacker-controlled data to reach the DOM without neutralization, enabling script injection.
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Severity by source
AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
The Autoptimize plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'ao_post_preload' meta value in all versions up to, and including, 3.1.14. This is due to insufficient input sanitization in the ao_metabox_save() function and missing output escaping when the value is rendered into a <link> tag in autoptimizeImages.php. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page, granted the "Image optimization" or "Lazy-load images" setting is enabled in the plugin configuration.
Executive ViewAI
Organizations using all should be aware of moderate risk from CVE-2026-2352, a cross-site scripting vulnerability rated CVSS 6.4. Attackers could inject scripts to steal sessions or perform actions as authenticated users. Organizations should apply vendor updates when available and monitor for exploitation.
Apply vendor patch. If patching is delayed: implement CSP headers, enable HttpOnly cookies, deploy WAF XSS rules.
Threat Intelligence Overview
NVD
CVE.org
EPSS
Vulnrichment
VulDB
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Cross-Site Scripting occurs when an application accepts untrusted data and sends it to a web browser without proper validation or encoding.
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Exploit-DB