CVE-2020-5231 is a medium-severity (CVSS 6.5) CWE-285 vulnerability in org.opencastproject:opencast-kernel. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether CVE-2020-5231 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Users with ROLE_COURSE_ADMIN can create new users in Opencast
Real-World Exposure
org.opencastproject:opencast-kernel☕org.opencastproject:opencast-kernelReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
In Opencast before 7.6 and 8.1, users with the role ROLE_COURSE_ADMIN can use the user-utils endpoint to create new users not including the role ROLE_ADMIN. ROLE_COURSE_ADMIN is a non-standard role in Opencast which is referenced neither in the documentation nor in any code (except for tests) but only in the security configuration. From the name – implying an admin for a specific course – users would never expect that this role allows user creation. This issue is fixed in 7.6 and 8.1 which both ship a new default security configuration.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.opencastproject:opencast-kernel | all versions | 7.6 |
| ☕Maven | org.opencastproject:opencast-kernel | ≥ 8.0&&< 8.1 | 8.1 |
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 org.opencastproject:opencast-kernel. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update org.opencastproject:opencast-kernel to 7.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-5231 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 pinpoints whether CVE-2020-5231 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2020-5231. 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-2020-5231 in your dependencies?
O3 detects CVE-2020-5231 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.