CVE-2021-29484
DOM XSS in Theme Preview
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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. Ghost(Pro) has already been patched. We can find no evidence that the issue was exploited on Ghost(Pro) prior to the patch being added. Self-hosters are impacted if running Ghost a version between 4.0.0 and 4.3.2. Immediate action should be taken to secure your site. The issue has been fixed in 4.3.3, all 4.x sites should upgrade as soon as possible. As the endpoint is unused, the patch simply removes it. As a workaround blocking access to /ghost/preview can also mitigate the issue.
Timeline
ID reserved
By GitHub_M
- 30 days later
· 30 days later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium6.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N |
| NVDNVD · Modified | 3.1 | Medium6.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N |
- EPSS (exploitation in 30 days)
- 7.9% · top 5.2% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.8.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
References (4)
- https://github.com/TryGhost/Ghost/security/advisories/GHSA-9fgx-q25h-jxrg (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://forum.ghost.org/t/critical-security-update-available-for-ghost-4-x/22290 (opens in a new tab)x_refsource_MISCx_transferred
- https://www.npmjs.com/package/ghost (opens in a new tab)x_refsource_MISCx_transferred
- https://blog.sonarsource.com/ghost-admin-takeover (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-9fgx-q25h-jxrg (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-29484)Record last updated .