Summary
Improper Validation of Certificate with Host Mismatch in Jenkins Mailer Plugin
Jenkins Mailer Plugin prior to 1.32.1, 1.31.1, and 1.29.1 does not perform hostname validation when connecting to the configured SMTP server. This lack of validation could be abused using a man-in-the-middle attack to intercept these connections.
Mailer Plugin 1.32.1, 1.31.1, and 1.29.1 validates the SMTP hostname when connecting via TLS by default. In Mailer Plugin 1.32 and earlier, administrators can set the Java system property mail.smtp.ssl.checkserveridentity to true on startup to enable this protection.
In case of problems, this protection can be disabled again by setting the Java system property mail.smtp.ssl.checkserveridentity to false on startup.
Impact
CVE-2020-2252 has a CVSS score of 4.8 (Medium). 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 (1.32.1, 1.31.1, 1.29.1); 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:mailer to 1.32.1 or later; org.jenkins-ci.plugins:mailer to 1.31.1 or later; org.jenkins-ci.plugins:mailer to 1.29.1 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2020-2252? CVE-2020-2252 is a medium-severity security vulnerability in org.jenkins-ci.plugins:mailer (maven), affecting versions = 1.32. It is fixed in 1.32.1, 1.31.1, 1.29.1.
- How severe is CVE-2020-2252? CVE-2020-2252 has a CVSS score of 4.8 (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 org.jenkins-ci.plugins:mailer are affected by CVE-2020-2252? org.jenkins-ci.plugins:mailer (maven) versions = 1.32 is affected.
- Is there a fix for CVE-2020-2252? Yes. CVE-2020-2252 is fixed in 1.32.1, 1.31.1, 1.29.1. Upgrade to this version or later.
- Is CVE-2020-2252 exploitable, and should I be worried? Whether CVE-2020-2252 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-2020-2252 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-2020-2252?
- Upgrade
org.jenkins-ci.plugins:mailerto 1.32.1 or later - Upgrade
org.jenkins-ci.plugins:mailerto 1.31.1 or later - Upgrade
org.jenkins-ci.plugins:mailerto 1.29.1 or later
- Upgrade