CVE-2026-24778 is a high-severity (CVSS 8.8) Cross-site Scripting (XSS) vulnerability in ghost. A fix is available for ghost — see the affected versions and patch details below.
Ghost vulnerable to XSS via malicious Portal preview links
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-24778.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-24778 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,238 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
ghostnpm@tryghost/portalnpmDescription
Ghost is an open source content management system. In Ghost versions 5.43.0 through 5.12.04 and 6.0.0 through 6.14.0, an attacker was able to craft a malicious link that, when accessed by an authenticated staff user or member, would execute JavaScript with the victim's permissions, potentially leading to account takeover. Ghost Portal versions 2.29.1 through 2.51.4 and 2.52.0 through 2.57.0 were vulnerable to this issue. Ghost automatically loads the latest patch of the members Portal component via CDN. For Ghost 5.x users, upgrading to v5.121.0 or later fixes the vulnerability. v5.121.0 loads Portal v2.51.5, which contains the patch. For Ghost 6.x users, upgrading to v6.15.0 or later fixes the vulnerability. v6.15.0 loads Portal v2.57.1, which contains the patch. For Ghost installations using a customized or self-hosted version of Portal, it will be necessary to manually rebuild from or update to the latest patch version.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | ghost | ≥ 5.43.0&&< 5.121.0 | 5.121.0npm install ghost@5.121.0 |
| 📦npm | @tryghost/portal | ≥ 2.29.1&&< 2.51.5 | 2.51.5npm install @tryghost/portal@2.51.5 |
| 📦npm | @tryghost/portal | ≥ 2.52.0&&< 2.57.1 | 2.57.1npm install @tryghost/portal@2.57.1 |
| 📦npm | ghost | ≥ 6.0.0&&< 6.15.0 | 6.15.0npm install ghost@6.15.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ghost, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update ghost to 5.121.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-24778 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-24778 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-24778. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-24778 in your dependencies?
O3 Security finds CVE-2026-24778 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.