Quick answers
- Is CVE-2026-105643 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-105643 being exploited in the wild.
- How severe is CVE-2026-105643?
- High severity, with a CVSS score of 7.3, published 5 October 2026.
- Which products and versions are affected?
- Ghost 6.34.0 to 6.66.0; ghost (npm) >= 6.34.0, < 6.67.0, SEMVER:introduced=6.34.0,fixed=6.67.0.
- Is there a fix for CVE-2026-105643?
- Yes. ghost (npm): upgrade to 6.67.0 or later. Until then: Self-hosted Ghost instances should ensure the security.embedPreviewUrl configuration option is left at its default value to disable unsafe embed previews. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-105643 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-105643?
- Check whether you run Ghost or ghost (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- ghost (npm): upgrade to 6.67.0 or later
npm install ghost@6.67.0
Self-hosted Ghost instances should ensure the security.embedPreviewUrl configuration option is left at its default value to disable unsafe embed previews.
Technical details
A stored cross-site scripting (XSS) vulnerability exists in the embed card preview feature of Ghost, which fails to properly sanitize user input before rendering it. An attacker with staff privileges can inject malicious scripts into post content via embed cards; when another staff member opens the affected post in the editor, the script executes in their browser context with their privileges. This could lead to session hijacking or privilege escalation.
Affected products
- Ghost Ghost 6.34.0 to 6.66.0
Identifiers
- CVE-2026-105643
- GHSA-69qc-f5m6-889c
Timeline
- 2026-10-01: disclosed
- 2026-10-05: advisory
- 2026-10-05: patched