SB2019121822 - Multiple vulnerabilities in WebSphere Deployer plugin for Jenkins

Description

This security bulletin contains information about 4 secuirty vulnerabilities.

1) Improper access control (CVE-ID: CVE-2019-16559)

The vulnerability allows a remote user to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to the affected software does not perform permission checks in methods performing form validation. A remote user with Overall/Read access can perform connection tests, determine whether files with an attacker-specified path exist on the Jenkins master file system, and obtain limited information about the Jenkins and plugin configuration based on the responses.

2) Improper Certificate Validation (CVE-ID: CVE-2019-16561)

The vulnerability allows a remote attacker to perform a man-in-the-middle (MiTM) attack.

The vulnerability exists due to the affected software unconditionally disables SSL/TLS certificate validation for the entire Jenkins master JVM. A remote user with Overall/Read access can supply a specially crafted SSL/TLS certificate, conduct man-in-the-middle attacks and disable SSL/TLS certificate and hostname validation for the entire Jenkins master JVM, or specify a new Java keystore from a file stored on the Jenkins master filesystem.

3) Cross-site scripting (CVE-ID: CVE-2019-16560)

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website, such as perform connection tests, determine whether files with an attacker-specified path exist on the Jenkins master file system, and obtain limited information about the Jenkins and plugin configuration based on the responses.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

4) XML External Entity injection (CVE-ID: CVE-2020-2108)

The vulnerability allows a remote user to gain access to sensitive information.

The vulnerability exists due to insufficient validation of user-supplied XML input. A remote user with Job/Configure permissions can pass a specially crafted war file containing a "WEB-INF/ibm-web-ext.xml" which is parsed by the plugin and view contents of arbitrary files on the system or initiate requests to external systems.

Successful exploitation of the vulnerability may allow an attacker to view contents of arbitrary file on the server or perform network scanning of internal and external infrastructure.

Remediation

Cybersecurity Help is not aware of any official remediation provided by the vendor.

References

• https://jenkins.io/security/advisory/2019-12-17/#SECURITY-1371
• https://jenkins.io/security/advisory/2019-12-17/#SECURITY-1581
• http://www.openwall.com/lists/oss-security/2020/01/29/1
• https://jenkins.io/security/advisory/2020-01-29/#SECURITY-1719