Summary
Sandbox bypass vulnerability in Jenkins Script Security Plugin
Jenkins Script Security Plugin provides a sandbox feature that allows low privileged users to define scripts, including Pipelines, that are generally safe to execute. Calls to code defined inside a sandboxed script are intercepted, and various allowlists are checked to determine whether the call is to be allowed.
In Script Security Plugin 1.75 and 1.66.5, any calls from outside a sandboxed script to code defined inside a sandboxed script were always allowed. As sandboxed scripts can communicate their results through script return values and similar mechanisms, this could result in code defined inside of a sandboxed script to be called without sandbox protection.
This vulnerability allows attackers with permission to define and run sandboxed scripts, including Pipelines, to bypass the sandbox protection and execute arbitrary code in the context of the Jenkins controller JVM.
Script Security Plugin 1.75 and 1.66.5 will prevent code defined inside a sandbox from being invoked outside a sandboxed script.
In rare cases, invocations of sandboxed scripts may begin failing if the script return value or script binding include code defined in the sandbox and is further processed by the calling code. To resolve this issue, the affected values need to be converted inside the sandboxed script to a known safe type, such as String.
For compatibility with this change, the following plugins should be upgraded to the versions specified:
- Email Extension Plugin should be updated to version 2.77 or newer.
- Warnings Next Generation Plugin should be updated to version 8.4.3 or newer.
- Warnings Plugin should be updated to version 5.0.2 or newer.
Impact
CVE-2020-2279 has a CVSS score of 9.9 (Critical). The vector is network-reachable, low 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 (1.75, 1.66.5); 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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org.jenkins-ci.plugins:script-security to 1.75 or later; org.jenkins-ci.plugins:script-security to 1.66.5 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2020-2279? CVE-2020-2279 is a critical-severity security vulnerability in org.jenkins-ci.plugins:script-security (maven), affecting versions >= 1.67, < 1.75. It is fixed in 1.75, 1.66.5.
- How severe is CVE-2020-2279? CVE-2020-2279 has a CVSS score of 9.9 (Critical). 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 org.jenkins-ci.plugins:script-security are affected by CVE-2020-2279? org.jenkins-ci.plugins:script-security (maven) versions >= 1.67, < 1.75 is affected.
- Is there a fix for CVE-2020-2279? Yes. CVE-2020-2279 is fixed in 1.75, 1.66.5. Upgrade to this version or later.
- Is CVE-2020-2279 exploitable, and should I be worried? Whether CVE-2020-2279 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-2020-2279 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-2020-2279?
- Upgrade
org.jenkins-ci.plugins:script-securityto 1.75 or later - Upgrade
org.jenkins-ci.plugins:script-securityto 1.66.5 or later
- Upgrade