CVE-2018-9861 — ckeditor-dev
MEDIUMCVE-2018-9861 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in ckeditor-dev. A fix is available for ckeditor-dev — see the affected versions and patch details below.
Enhanced Image plugin for CKEditor is vulnerable to Cross-site scripting (XSS)
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-2018-9861 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 377,166 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, a proxy for how much of the ecosystem is exposed.
ckeditor-devnpmDescription
Cross-site scripting (XSS) vulnerability in the Enhanced Image (aka image2) plugin for CKEditor (in versions 4.5.10 through 4.9.1; fixed in 4.9.2), as used in Drupal 8 before 8.4.7 and 8.5.x before 8.5.2 and other products, allows remote attackers to inject arbitrary web script through a crafted IMG element.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | ckeditor-dev | ≥ 4.5.10&&< 4.9.2 | 4.9.2npm install ckeditor-dev@4.9.2 |
| 🐘Packagist | drupal/core | ≥ 8.5.0&&< 8.5.2 | 8.5.2composer require drupal/core:^8.5.2 |
| 🐘Packagist | drupal/core | ≥ 8.0&&< 8.4.7 | 8.4.7composer require drupal/core:^8.4.7 |
| 🐘Packagist | drupal/drupal | ≥ 8.0&&< 8.4.7 | 8.4.7composer require drupal/drupal:^8.4.7 |
| 🐘Packagist | drupal/drupal | ≥ 8.5&&< 8.5.2 | 8.5.2composer require drupal/drupal:^8.5.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ckeditor-dev, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update ckeditor-dev to 4.9.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-9861 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-2018-9861 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2018-9861. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Frequently Asked Questions
Is CVE-2018-9861 in your dependencies?
O3 Security finds CVE-2018-9861 across npm, Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.