CVE-2023-30943 is a medium-severity (CVSS 6.5) CWE-73 vulnerability in moodle/moodle. 4 public exploit references exist, so weaponization risk is real. A fix is available for moodle/moodle — see the affected versions and patch details below.
Moodle: tinymce loaders susceptible to arbitrary folder creation
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-2023-30943 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 377,636 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
moodle/moodleReal-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
The vulnerability was found Moodle which exists because the application allows a user to control path of the older to create in TinyMCE loaders. A remote user can send a specially crafted HTTP request and create arbitrary folders on the system.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | moodle/moodle | all versions | 4.2.0-rc2composer require moodle/moodle:^4.2.0-rc2 |
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 moodle/moodle, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update moodle/moodle to 4.2.0-rc2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-30943 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-2023-30943 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-30943. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
How to detect CVE-2023-30943
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2023-30943 -u https://target- Template
- Moodle - Cross-Site Scripting/Remote Code Execution
- Severity
- medium
- Impact
- Successful exploitation of these vulnerabilities could lead to unauthorized access, data theft, and potential compromise of the Moodle application and its users.
- Remediation
- Apply the latest security patches and updates from the vendor to address this vulnerability.
Template by ProjectDiscovery nuclei-templates (ritikchaddha), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2023-30943 in your dependencies?
O3 Security finds CVE-2023-30943 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.