CVE-2021-41258

{"id": "CVE-2021-41258", "metrics": {"cvssMetricV2": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"version": "2.0", "baseScore": 2.1, "accessVector": "NETWORK", "vectorString": "AV:N/AC:H/Au:S/C:N/I:P/A:N", "authentication": "SINGLE", "integrityImpact": "PARTIAL", "accessComplexity": "HIGH", "availabilityImpact": "NONE", "confidentialityImpact": "NONE"}, "acInsufInfo": false, "impactScore": 2.9, "baseSeverity": "LOW", "obtainAllPrivilege": false, "exploitabilityScore": 3.9, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": true}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 5.4, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "LOW"}, "impactScore": 2.7, "exploitabilityScore": 2.3}, {"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.3, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 2.1}]}, "published": "2021-11-16T18:15:07.587", "references": [{"url": "https://github.com/getkirby/kirby/pull/3510", "tags": ["Patch", "Third Party Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/getkirby/kirby/releases/tag/3.5.8", "tags": ["Release Notes", "Third Party Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/getkirby/kirby/security/advisories/GHSA-cq58-r77c-5jjw", "tags": ["Third Party Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-79"}]}, {"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-79"}]}], "descriptions": [{"lang": "en", "value": "Kirby is an open source file structured CMS. In affected versions Kirby's blocks field stores structured data for each block. This data is then used in block snippets to convert the blocks to HTML for use in your templates. We recommend to escape HTML special characters to protect against cross-site scripting (XSS) attacks. The default snippet for the image block unfortunately did not use our escaping helper. This made it possible to include malicious HTML code in the source, alt and link fields of the image block, which would then be displayed on the site frontend and executed in the browsers of site visitors and logged in users who are browsing the site. Attackers must be in your group of authenticated Panel users in order to exploit this weakness. Users who do not make use of the blocks field are not affected. This issue has been patched in Kirby version 3.5.8 by escaping special HTML characters in the output from the default image block snippet. Please update to this or a later version to fix the vulnerability."}, {"lang": "es", "value": "Kirby es un CMS estructurado de archivos de c\u00f3digo abierto. En las versiones afectadas, el campo blocks de Kirby almacena datos estructurados para cada bloque. Estos datos son usados en los fragmentos de bloque para convertir los bloques a HTML para ser usados en sus plantillas. Recomendamos escapar los caracteres especiales de HTML para protegerse de los ataques de tipo cross-site scripting (XSS). Lamentablemente, el fragmento predeterminado para el bloque de im\u00e1genes no usaba nuestro ayudante de escape. Esto permit\u00eda incluir c\u00f3digo HTML malicioso en los campos source, alt y link del bloque de imagen, que luego se mostrar\u00eda en el frontend del sitio y se ejecutar\u00eda en los navegadores de los visitantes del sitio y de los usuarios registrados que estuvieran navegando por \u00e9l. Los atacantes deben estar en su grupo de usuarios autenticados del Panel para poder explotar esta debilidad. Los usuarios que no hacen uso del campo blocks no est\u00e1n afectados. Este problema ha sido parcheado en la versi\u00f3n 3.5.8 de Kirby al escapar los caracteres HTML especiales en la salida del fragmento de bloque de imagen por defecto. Por favor, actualice a esta versi\u00f3n o a una posterior para corregir la vulnerabilidad"}], "lastModified": "2021-11-18T17:27:49.483", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:getkirby:kirby:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "092FA583-2B21-4F4A-8C68-43DE0C504FC8", "versionEndIncluding": "3.5.7.1", "versionStartIncluding": "3.5.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}