CVE-2026-6397

[cvmh-sticky readmoretext='"><img src=x onerror=alert(1)>'] // Explanation: Injecting a malicious payload into the 'readmoretext' attribute. // The payload closes the existing attribute and injects an img tag with onerror event to execute JS. // This requires Contributor-level privileges to post.

{"cve": {"id": "CVE-2026-6397", "sourceIdentifier": "[email protected]", "published": "2026-05-20T02:16:37.770", "lastModified": "2026-05-20T13:54:54.890", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "The Sticky plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the `cvmh-sticky` shortcode `readmoretext` attribute in versions up to and including 2.5.6. This is due to insufficient input sanitization and output escaping in the `cvmh_sticky_front_render()` function — the `readmoretext` attribute value is passed through `apply_filters()` and directly concatenated into the HTML output without any escaping function such as `esc_html()`. 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 a page containing the injected 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/sticky/tags/2.5.6/includes/functions.php#L118", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/sticky/tags/2.5.6/includes/shortcode.php#L7", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/sticky/trunk/includes/functions.php#L118", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/sticky/trunk/includes/shortcode.php#L7", "source": "[email protected]"}, {"url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/135783c5-8175-4775-a013-f1e2bef04479?source=cve", "source": "[email protected]"}]}}