CVE-2019-0071 Explained : Impact and Mitigation
Discover the impact of CVE-2019-0071 on Juniper Networks Junos OS versions 18.1R3-S4 and 18.3R1-S3. Learn about the vulnerability, its technical details, and mitigation steps to secure your systems.
Veriexec is a file integrity subsystem within Junos OS that operates at the kernel level, guaranteeing the execution of only authorized binaries. However, certain versions of Junos OS, specifically those found on specific EX Series platforms, contain a flaw that prevents the Veriexec subsystem from initializing properly. This vulnerability impacts Juniper Networks Junos OS versions 18.1R3-S4 on EX2300, EX2300-C, and EX3400, as well as 18.3R1-S3 on EX2300, EX2300-C, and EX3400.
Understanding CVE-2019-0071
This CVE involves a vulnerability in Junos OS that allows a locally authenticated user with shell access to install untrusted executable images and escalate privileges to gain complete control over the system.
What is CVE-2019-0071?
- Veriexec subsystem in Junos OS fails to initialize properly on specific EX Series platforms
- Locally authenticated user with shell access can exploit the flaw to install untrusted executable images
- Affected versions: 18.1R3-S4 and 18.3R1-S3 on EX2300, EX2300-C, and EX3400
The Impact of CVE-2019-0071
- CVSS Score: 7.8 (High)
- Attack Vector: Local
- Confidentiality Impact: High
- Integrity Impact: High
- Availability Impact: High
Technical Details of CVE-2019-0071
This section provides detailed technical information about the vulnerability.
Vulnerability Description
- Flaw in specific Junos OS versions prevents Veriexec subsystem initialization
- Allows unauthorized installation of executable images by authenticated users
Affected Systems and Versions
- Platforms: EX2300, EX2300-C, EX3400
- Vulnerable Versions: 18.1R3-S4, 18.3R1-S3
Exploitation Mechanism
- Locally authenticated user with shell access can exploit the flaw
- Console error messages indicate the failure of Veriexec subsystem initialization
Mitigation and Prevention
It is crucial to take immediate steps to mitigate the risks posed by CVE-2019-0071.
Immediate Steps to Take
- Limit access to the Junos shell to trusted administrators
- Upgrade to the following software releases to resolve the issue: 18.1R3-S5, 18.3R1-S4, and all subsequent releases
Long-Term Security Practices
- Regularly monitor and update Junos OS to the latest patched versions
- Implement strong access controls and user permissions
Patching and Updates
- Juniper Networks strongly recommends upgrading to an updated release of Junos OS to address this vulnerability