What is CVE-2021-4250?

CVE-2021-4250 is a high-severity security vulnerability in active_attr (rubygems), affecting versions < 0.15.4. It is fixed in 0.15.4.

How severe is CVE-2021-4250?

CVE-2021-4250 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.

Which versions of active_attr are affected by CVE-2021-4250?

active_attr (rubygems) versions < 0.15.4 is affected.

Is there a fix for CVE-2021-4250?

Yes. CVE-2021-4250 is fixed in 0.15.4. Upgrade to this version or later.

Is CVE-2021-4250 exploitable, and should I be worried?

Whether CVE-2021-4250 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.

What actually determines whether CVE-2021-4250 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.

CVE-2021-4250 in active_attr

Q: How severe is CVE-2021-4250?

CVE-2021-4250 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.

Q: Which versions of active_attr are affected by CVE-2021-4250?

active_attr (rubygems) versions < 0.15.4 is affected.

Q: Is there a fix for CVE-2021-4250?

Yes. CVE-2021-4250 is fixed in 0.15.4. Upgrade to this version or later.

Q: Is CVE-2021-4250 exploitable, and should I be worried?

Whether CVE-2021-4250 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.

Q: What actually determines whether CVE-2021-4250 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.

Q: How do I fix CVE-2021-4250?

Upgrade active_attr to 0.15.4 or later.

Summary

active_attr Improper Resource Shutdown or Release vulnerability

A vulnerability classified as problematic has been found in cgriego active_attr up to 0.15.3. This affects the function call of the file lib/active_attr/typecasting/boolean_typecaster.rb of the component Regex Handler. The manipulation of the argument value leads to denial of service. The exploit has been disclosed to the public and may be used. Upgrading to version 0.15.4 can address this issue. The name of the patch is dab95e5843b01525444b82bd7b336ef1d79377df. It is recommended to upgrade the affected component. The associated identifier of this vulnerability is VDB-216207.

Impact

CVE-2021-4250 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 (0.15.4); upgrading removes the vulnerable code path.

Affected versions

active_attr (< 0.15.4)

Security releases

active_attr → 0.15.4 (rubygems)

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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Remediation advice

Upgrade active_attr to 0.15.4 or later to resolve this vulnerability.

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is CVE-2021-4250? CVE-2021-4250 is a high-severity security vulnerability in active_attr (rubygems), affecting versions < 0.15.4. It is fixed in 0.15.4.
How severe is CVE-2021-4250? CVE-2021-4250 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.
Which versions of active_attr are affected by CVE-2021-4250? active_attr (rubygems) versions < 0.15.4 is affected.
Is there a fix for CVE-2021-4250? Yes. CVE-2021-4250 is fixed in 0.15.4. Upgrade to this version or later.
Is CVE-2021-4250 exploitable, and should I be worried? Whether CVE-2021-4250 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-2021-4250 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-2021-4250? Upgrade active_attr to 0.15.4 or later.