Summary
actionpack CRLF injection vulnerability
CRLF injection vulnerability in actionpack/lib/action_controller/response.rb in Ruby on Rails 2.3.x before 2.3.13 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via the Content-Type header.
Impact
Untrusted input is evaluated as executable code within the application's runtime environment. Typical impact: arbitrary code execution within the application's privilege context.
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-2011-3186? CVE-2011-3186 is a medium-severity code injection vulnerability in actionpack (rubygems), affecting versions >= 2.3.0, < 2.3.13. It is fixed in 2.3.13. Untrusted input is evaluated as executable code within the application's runtime environment.
- Which versions of actionpack are affected by CVE-2011-3186? actionpack (rubygems) versions >= 2.3.0, < 2.3.13 is affected.
- Is there a fix for CVE-2011-3186? Yes. CVE-2011-3186 is fixed in 2.3.13. Upgrade to this version or later.
- Is CVE-2011-3186 exploitable, and should I be worried? Whether CVE-2011-3186 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-2011-3186 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-2011-3186? Upgrade
actionpackto 2.3.13 or later.