CVE-2020-2232 in Email Extension Plugin
Summary
by MITRE
Jenkins Email Extension Plugin 2.72 and 2.73 transmits and displays the SMTP password in plain text as part of the global Jenkins configuration form, potentially resulting in its exposure.
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Analysis
by VulDB Data Team • 11/08/2020
The vulnerability identified as CVE-2020-2232 affects the Jenkins Email Extension Plugin version 2.72 and 2.73, representing a critical security flaw in how sensitive authentication credentials are handled within the Jenkins continuous integration and delivery platform. This issue manifests when administrators configure email notifications through the global Jenkins configuration form, where the SMTP password is displayed in plaintext rather than being masked or properly secured. The vulnerability exposes a fundamental weakness in credential handling practices that directly violates established security principles for protecting sensitive information in enterprise environments.
The technical flaw stems from improper input validation and output sanitization within the plugin's configuration interface. When users navigate to the global configuration settings to establish email notification parameters, the system fails to mask the SMTP password field, instead displaying the complete credential in plain text format. This design oversight creates an immediate exposure risk where any individual with access to the Jenkins web interface can observe the password in cleartext, potentially including unauthorized users who gain access to the system through other attack vectors. The vulnerability directly maps to CWE-522, which addresses insufficiently protected credentials, and represents a failure in implementing proper authentication credential management practices as outlined in security frameworks such as NIST SP 800-63B.
The operational impact of this vulnerability extends beyond simple credential exposure, creating multiple attack surface opportunities for malicious actors seeking to compromise Jenkins environments. An attacker who gains access to the Jenkins web interface can immediately extract the SMTP password and potentially use it to authenticate to external email servers, establish unauthorized email communication channels, or even escalate privileges within the email infrastructure. The exposure of SMTP credentials also enables attackers to conduct phishing campaigns or send malicious emails from the compromised Jenkins environment, potentially affecting the organization's reputation and security posture. This vulnerability significantly increases the risk of supply chain attacks, as compromised email credentials could be used to manipulate Jenkins notifications and communications with external systems, aligning with tactics described in the MITRE ATT&CK framework under T1190 for exploitation of remote services.
Organizations utilizing affected Jenkins versions must implement immediate remediation measures to address this vulnerability, including upgrading to patched versions of the Email Extension Plugin where the password field is properly masked and secured. The recommended mitigation strategy involves not only updating the plugin but also implementing additional security controls such as restricting access to the Jenkins web interface through network segmentation, implementing strong authentication mechanisms, and establishing proper credential rotation procedures. Security teams should also conduct comprehensive audits of all Jenkins configurations to identify any additional exposed credentials and ensure that all authentication information is properly protected through encryption and access control measures. The vulnerability demonstrates the critical importance of proper credential handling in CI/CD environments where systems often contain privileged access to production infrastructure and sensitive organizational data.