CVE-2021-0264 : Exploit Details and Defense Strategies
Find out about CVE-2021-0264, a vulnerability in Juniper Networks Junos OS that can lead to a Denial of Service condition. Learn the impact, affected systems, and mitigation steps.
A vulnerability in the processing of traffic matching a firewall filter containing a syslog action in Juniper Networks Junos OS on MX Series with MPC10/MPC11 cards installed, PTX10003, and PTX10008 Series devices, can cause the line card to crash and restart, resulting in a Denial of Service (DoS) condition. This vulnerability affects specific versions of Junos OS and Junos OS Evolved.
Understanding CVE-2021-0264
This section will provide insights into the impact, technical details, and mitigation strategies related to CVE-2021-0264.
What is CVE-2021-0264?
CVE-2021-0264 is a vulnerability in Juniper Networks Junos OS that can lead to a Denial of Service (DoS) condition when traffic matching a specific firewall filter hits a line card with syslog action configured.
The Impact of CVE-2021-0264
The vulnerability can cause affected line cards to crash and restart, impacting traffic processing and leading to a sustained Denial of Service (DoS) condition. It affects MX Series routers with specific line cards and PTX10003/PTX10008 Series routers.
Technical Details of CVE-2021-0264
This section will delve into the vulnerability description, affected systems and versions, as well as the exploitation mechanism.
Vulnerability Description
The vulnerability arises from the processing of traffic matching a firewall filter with syslog action, causing affected line cards to crash and restart, leading to a DoS scenario.
Affected Systems and Versions
MX Series routers with MPC10/MPC11 line cards running specific Junos OS versions and PTX10003/PTX10008 Series devices are impacted by this vulnerability.
Exploitation Mechanism
There is no known instance of malicious exploitation of this vulnerability according to Juniper SIRT.
Mitigation and Prevention
This section focuses on immediate steps to take, long-term security practices, and patching and updates.
Immediate Steps to Take
Remove the "syslog" action from the firewall filter configuration to mitigate the vulnerability.
Long-Term Security Practices
Regularly update Junos OS to the fixed versions provided by Juniper Networks to ensure the system is protected against this vulnerability.
Patching and Updates
Juniper Networks has released software updates to address this specific vulnerability. Ensure you upgrade to the recommended versions.