Summary
All request mappings in StreamingCoordinatorController.java handling /kylin/api/streaming_coordinator/* REST API endpoints did not include any security checks, which allowed an unauthenticated user to issue arbitrary requests, such as assigning/unassigning of streaming cubes, creation/modification and deletion of replica sets, to the Kylin Coordinator. For endpoints accepting node details in HTTP message body, unauthenticated (but limited) server-side request forgery (SSRF) can be achieved. This issue affects Apache Kylin Apache Kylin 3 versions prior to 3.1.2.
Impact
Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside. Typical impact: access to internal metadata services, internal APIs, or cloud credentials.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
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. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2021-27738? CVE-2021-27738 is a medium-severity server-side request forgery (SSRF) vulnerability in org.apache.kylin:kylin (maven), affecting versions < 3.1.3. It is fixed in 3.1.3. Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside.
- Which versions of org.apache.kylin:kylin are affected by CVE-2021-27738? org.apache.kylin:kylin (maven) versions < 3.1.3 is affected.
- Is there a fix for CVE-2021-27738? Yes. CVE-2021-27738 is fixed in 3.1.3. Upgrade to this version or later.
- Is CVE-2021-27738 exploitable, and should I be worried? Whether CVE-2021-27738 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
- What actually determines whether CVE-2021-27738 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.
- How do I fix CVE-2021-27738? Upgrade
org.apache.kylin:kylinto 3.1.3 or later.