CVE-2020-5206 is a critical-severity (CVSS 10) CWE-285 vulnerability in org.opencastproject:opencast-kernel. A fix is available for org.opencastproject:opencast-kernel — see the affected versions and patch details below.
Authentication Bypass For Endpoints With Anonymous Access in Opencast
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-2020-5206 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 378,567 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
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
Impact
Using a remember-me cookie with an arbitrary username can cause Opencast to assume proper authentication for that user even if the remember-me cookie was incorrect given that the attacked endpoint also allows anonymous access.
This way, an attacker can, for example, fake a remember-me token, assume the identity of the global system administrator and request non-public content from the search service without ever providing any proper authentication.
Patches
This problem is fixed in Opencast 7.6 and Opencast 8.1
Workarounds
As a workaround for older, unpatched versions, disabling remember-me cookies in etc/security/mh_default_org.xml will mitigate the problem but will obviously also disable this feature without obvious indication. To deactivate this, remove the following line from the security configuration:
<sec:remember-me … />
References
For more information
If you have any questions or comments about this advisory:
- Open an issue in opencast/opencast
- For security-relevant information, email us at [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.opencastproject:opencast-kernel | all versions | 7.6org.opencastproject:opencast-kernel:7.6 |
| ☕Maven | org.opencastproject:opencast-kernel | ≥ 8.0&&< 8.1 | 8.1org.opencastproject:opencast-kernel:8.1 |
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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
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-2020-5206 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-2020-5206 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2020-5206. 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-2020-5206 in your dependencies?
O3 Security finds CVE-2020-5206 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.