Summary
Execution of untrusted code through config file
Workarounds
Manually adjust yaml.load() to yaml.safe_load()
For more information
If you have any questions or comments about this advisory:
- Open an issue in tenable/integration-jira-cloud
- Email us at [email protected]
Impact
It is possible to run arbitrary commands through the yaml.load() method. This could allow an attacker with local access to the host to run arbitrary code by running the application with a specially crafted YAML configuration file.
Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect. Typical impact: arbitrary code execution or logic abuse.
CVE-2021-21371 has a CVSS score of 5.0 (Medium). The vector is requires local access, no privileges required, and user interaction required. 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 (1.1.21); upgrading removes the vulnerable code path.
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.
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Frequently Asked Questions
- What is CVE-2021-21371? CVE-2021-21371 is a medium-severity insecure deserialization vulnerability in tenable-jira-cloud (pip), affecting versions < 1.1.21. It is fixed in 1.1.21. Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect.
- How severe is CVE-2021-21371? CVE-2021-21371 has a CVSS score of 5.0 (Medium). 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.
- Which versions of tenable-jira-cloud are affected by CVE-2021-21371? tenable-jira-cloud (pip) versions < 1.1.21 is affected.
- Is there a fix for CVE-2021-21371? Yes. CVE-2021-21371 is fixed in 1.1.21. Upgrade to this version or later.
- Is CVE-2021-21371 exploitable, and should I be worried? Whether CVE-2021-21371 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-2021-21371 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-2021-21371? Upgrade
tenable-jira-cloudto 1.1.21 or later.