id: CVE-2021-29484 info: name: DOM XSS in Ghost CMS author: rootxharsh,iamnoooob severity: medium description: Ghost is a Node.js CMS. An unused endpoint added during the development of 4.0.0 has left sites vulnerable to untrusted users gaining access to Ghost Admin. Attackers can gain access by getting logged in users to click a link containing malicious code. Users do not need to enter credentials and may not know they've visited a malicious site. reference: - https://github.com/TryGhost/Ghost/security/advisories/GHSA-9fgx-q25h-jxrg - https://nvd.nist.gov/vuln/detail/CVE-2021-29484 - https://www.npmjs.com/package/ghost - https://forum.ghost.org/t/critical-security-update-available-for-ghost-4-x/22290 classification: cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N cvss-score: 6.1 cve-id: CVE-2021-29484 cwe-id: CWE-79 tags: cve,cve2021,xss,ghost requests: - method: GET path: - "{{BaseURL}}/ghost/preview" matchers-condition: and matchers: - type: word words: - 'XMLHttpRequest.prototype.open' part: body - type: word words: - 'text/html' part: header - type: status status: - 200