CVE-2021-0253 : Security Advisory and Response
Discover the impact of CVE-2021-0253 on Juniper Networks Junos OS NFX Series devices, its technical details, affected versions, exploitation mechanism, and mitigation steps to prevent privilege escalation.
NFX Series devices using Juniper Networks Junos OS are susceptible to a local command execution vulnerability that allows attackers to elevate their privileges via the Junos Device Management Daemon (JDMD) process.
Understanding CVE-2021-0253
This CVE identifies a vulnerability in Junos OS affecting NFX Series devices, allowing for potential privilege escalation through local command execution.
What is CVE-2021-0253?
CVE-2021-0253 relates to a flaw in Juniper Networks Junos OS that enables threat actors to execute commands locally and gain elevated privileges via the JDMD process.
The Impact of CVE-2021-0253
The impact of this vulnerability is categorized as high, with the ability for attackers to exploit the issue and potentially gain unauthorized access on affected systems.
Technical Details of CVE-2021-0253
The following details outline the specifics of this CVE.
Vulnerability Description
The vulnerability allows for local command execution on NFX Series devices running certain versions of Junos OS, leading to a risk of privilege escalation.
Affected Systems and Versions
Affected systems include NFX Series devices running specific versions prior to 18.3R3-S4, 18.4R2-S5, 18.4R3-S5, 19.1R1-S3, 19.1R2, 19.2R3, 19.3R3, and 19.4R2-S2 of Junos OS.
Exploitation Mechanism
Attack complexity is rated as low, with a high impact on confidentiality, integrity, and availability. The vulnerability requires low privileges to exploit and has a local attack vector.
Mitigation and Prevention
Learn how to address and prevent the CVE-2021-0253 vulnerability.
Immediate Steps to Take
Update Junos OS to versions 18.3R3-S4, 18.4R2-S5, 18.4R3-S5, 19.1R3-S3, 19.2R3, 19.3R3, 19.4R2-S2, 20.1R1, or later to resolve the issue.
Long-Term Security Practices
Implement access controls like access lists or firewall filters to restrict network access and reduce the risk of exploitation.
Patching and Updates
Regularly apply software patches and updates provided by Juniper Networks to stay protected against known vulnerabilities.