CVE-2026-4300

// Enter the following payload into the 'Loading Label' field in Robo Gallery settings: "|***alert(document.domain)***|"

{"cve": {"id": "CVE-2026-4300", "sourceIdentifier": "[email protected]", "published": "2026-04-08T10:16:01.953", "lastModified": "2026-04-24T18:05:09.240", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "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 output within an inline `<script>` tag via `renderMainBlock()` with the quote markers stripped — resulting in arbitrary JavaScript execution. The gallery post type uses `capability_type => 'post'`, allowing Author-level users to create galleries. This makes it possible for authenticated attackers, with Author-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses a page containing the gallery shortcode."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N", "baseScore": 6.4, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.1, "impactScore": 2.7}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-79"}]}], "references": [{"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/tags/5.1.3/includes/frontend/modules/base-grid/grid/grid.v1.php#L89", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/tags/5.1.3/includes/frontend/modules/base-grid/layout.v1.php#L101", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/tags/5.1.3/includes/frontend/modules/base-grid/layout.v1.php#L52", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/tags/5.1.3/includes/frontend/modules/class/jsoptions.php#L87", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/tags/5.1.3/includes/frontend/modules/class/jsoptions.php#L97", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/tags/5.1.3/includes/options/rbs_gallery_options_loading.php#L95", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/trunk/includes/frontend/modules/base-grid/grid/grid.v1.php#L89", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/trunk/includes/frontend/modules/base-grid/layout.v1.php#L101", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/trunk/includes/frontend/modules/base-grid/layout.v1.php#L52", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/trunk/includes/frontend/modules/class/jsoptions.php#L87", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/trunk/includes/frontend/modules/class/jsoptions.php#L97", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/robo-gallery/trunk/includes/options/rbs_gallery_options_loading.php#L95", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3488182%40robo-gallery&new=3488182%40robo-gallery&sfp_email=&sfph_mail=", "source": "[email protected]"}, {"url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/d8693b7d-693f-450a-89ef-e936a8813ca9?source=cve", "source": "[email protected]"}]}}