CVE-2026-4300
6.4 · MEDIUMOverview
CVE-2026-4300 is a medium-severity vulnerability. It was published on April 8, 2026 and has a CVSS 3.1 base score of 6.4 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 6.4, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
The Robo Gallery plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'Loading Label' setting in all versions up to, and including, 5.1.3. The plugin uses a custom `|***...***|` marker pattern in its `fixJsFunction()` method to embed raw JavaScript function references within JSON-encoded configuration objects. When a gallery's options are rendered on the frontend, `json_encode()` wraps all string values in double quotes. The `fixJsFunction()` method then strips the `"|***` and `***|"` sequences, effectively converting a JSON string value into raw JavaScript code. The Loading Label field (stored as `rbs_gallery_LoadingWord` post_meta) is an `rbstext` type field that is sanitized with `sanitize_text_field()` on save. While this strips HTML tags, it does not strip the `|***...***|` markers since they contain no HTML. When a user inputs `|***alert(document.domain)***|`, the value passes through sanitization intact, is stored in post_meta, and is later retrieved and out
Remediation
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
References
Frequently Asked Questions
What is CVE-2026-4300?
CVE-2026-4300 is a medium-severity vulnerability. It was published on April 8, 2026 and has a CVSS 3.1 base score of 6.4 (MEDIUM).
How severe is CVE-2026-4300?
This vulnerability has a CVSS 3.1 base score of 6.4, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-4300?
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-4300?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-4300 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
Automated penetration testing that runs continuously, not just quarterly.
AI-driven PR review catches vulnerable dependencies before they ship.
Browser-based exploitation validates findings with real proof-of-concept.
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