CVE-2020-10187

Exposure of Sensitive Information to an Unauthorized Actor in Doorkeeper

Workarounds

Patch Doorkeeper::Application model #as_json(options = {}) method and define only those attributes you want to expose.

Additional recommended hardening is to enable application secrets hashing (guide), available since Doorkeeper 5.1. This would render the exposed secret useless.

References

• Commit with fix: https://github.com/doorkeeper-gem/doorkeeper/commit/25d038022c2fcad45af5b73f9d003cf38ff491f6
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-10187

Information disclosure vulnerability. Allows an attacker to see all Doorkeeper::Application model attribute values (including secrets) using authorized applications controller if it's enabled (GET /oauth/authorized_applications.json).

The application does not perform an authorization check before performing a sensitive operation. Typical impact: unauthorized access to restricted functionality or data.

CVE-2020-10187 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (5.0.3, 5.1.1, 5.2.5, 5.3.2); upgrading removes the vulnerable code path.

Kodem intelligence

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These versions have the fix:

• 5.0.3
• 5.1.1
• 5.2.5
• 5.3.2

1. What is CVE-2020-10187? CVE-2020-10187 is a high-severity missing authorization vulnerability in doorkeeper (rubygems), affecting versions >= 5.0.0, < 5.0.3. It is fixed in 5.0.3, 5.1.1, 5.2.5, 5.3.2. The application does not perform an authorization check before performing a sensitive operation.
2. How severe is CVE-2020-10187? CVE-2020-10187 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of doorkeeper are affected by CVE-2020-10187? doorkeeper (rubygems) versions >= 5.0.0, < 5.0.3 is affected.
4. Is there a fix for CVE-2020-10187? Yes. CVE-2020-10187 is fixed in 5.0.3, 5.1.1, 5.2.5, 5.3.2. Upgrade to this version or later.
5. Is CVE-2020-10187 exploitable, and should I be worried? Whether CVE-2020-10187 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2020-10187 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2020-10187?
   • Upgrade doorkeeper to 5.0.3 or later
   • Upgrade doorkeeper to 5.1.1 or later
   • Upgrade doorkeeper to 5.2.5 or later
   • Upgrade doorkeeper to 5.3.2 or later

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