CVE-2018-5233 — getgrav/grav
MEDIUMCVE-2018-5233 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in getgrav/grav. 2 public exploit references exist, so weaponization risk is real. A fix is available for getgrav/grav — see the affected versions and patch details below.
Grav CMS Cross-site scripting (XSS) vulnerability
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-2018-5233 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
getgrav/gravReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Cross-site scripting (XSS) vulnerability in system/src/Grav/Common/Twig/Twig.php in Grav CMS before 1.3.0 allows remote attackers to inject arbitrary web script or HTML via the PATH_INFO to admin/tools.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | getgrav/grav | all versions | 1.3.0composer require getgrav/grav:^1.3.0 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getgrav/grav, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update getgrav/grav to 1.3.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-5233 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-2018-5233 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2018-5233. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
How to detect CVE-2018-5233
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2018-5233 -u https://target- Template
- Grav CMS <1.3.0 - Cross-Site Scripting
- Severity
- medium
- Impact
- Attackers can execute arbitrary JavaScript in victims' browsers, potentially stealing session cookies, administrative credentials, or performing actions on behalf of authenticated users.
- Remediation
- Upgrade Grav CMS to version 1.3.0 or later, which includes proper input sanitization to mitigate the XSS vulnerability.
Template by ProjectDiscovery nuclei-templates (pikpikcu), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2018-5233 in your dependencies?
O3 Security finds CVE-2018-5233 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.