CVE-2021-0270 : What You Need to Know
Discover in-depth insights into CVE-2021-0270, a critical vulnerability in Juniper Networks Junos OS impacting PTX Series and QFX10K Series devices, potentially leading to Denial of Service (DoS) situations. Learn about the impact, technical details, affected systems, and mitigation strategies.
A detailed analysis of CVE-2021-0270, a vulnerability found in Juniper Networks Junos OS affecting PTX Series and QFX10K Series devices with the "inline-jflow" feature enabled, potentially leading to a Denial of Service (DoS) situation.
Understanding CVE-2021-0270
This section provides an overview and impact analysis of the CVE-2021-0270 vulnerability.
What is CVE-2021-0270?
CVE-2021-0270 involves a use after free weakness in the Packet Forwarding Engine (PFE) microkernel architecture of Juniper Networks Junos OS, allowing attackers to trigger unexpected restarts of Flexible PIC Concentrators (FPCs), leading to potential DoS scenarios.
The Impact of CVE-2021-0270
The vulnerability has a CVSS base score of 7.5, indicating a high severity level with a low attack complexity, network-based attack vector, and high availability impact.
Technical Details of CVE-2021-0270
In this section, we delve into the specifics of the vulnerability.
Vulnerability Description
The vulnerability arises due to a race condition scenario in the PFE microkernel architecture, causing FPC restarts under certain network loads, potentially disrupting traffic and leading to sustained DoS situations.
Affected Systems and Versions
Juniper Networks Junos OS versions 18.1R2 and earlier, up to 18.1R3-S10, running on PTX Series and QFX10K Series devices with the "inline-jflow" feature enabled are susceptible to this vulnerability.
Exploitation Mechanism
Currently, there are no known instances of malicious exploitation of this vulnerability, as reported by Juniper SIRT.
Mitigation and Prevention
Explore the strategies to mitigate and prevent exploitation of CVE-2021-0270.
Immediate Steps to Take
If upgrading is not immediately possible, consider implementing a workaround by disabling the "inline-flow" feature to mitigate the risk.
Long-Term Security Practices
Ensure timely software updates to versions patched against CVE-2021-0270, including releases such as 16.1R7-S8, 17.2R3-S4, 17.3R3-S8, 17.4R2-S11, 17.4R3-S2, 18.1R3-S10, and 18.2R1.
Patching and Updates
Refer to Juniper's provided solutions and upgrade to the recommended software versions to address CVE-2021-0270.