CVE-2021-0215 : What You Need to Know

A memory leak vulnerability in Junos OS devices may lead to crash and restart of processes due to 802.1X authenticator port interface flaps.

Understanding CVE-2021-20657

This CVE involves a memory leak issue on Junos OS devices that can impact packet forwarding processes when the 802.1X authenticator port interface flaps.

What is CVE-2021-20657?

The vulnerability causes processes like pfex, which forward packets, to crash and restart on Junos OS devices when the 802.1X authenticator port interface flaps.

The Impact of CVE-2021-20657

The memory leak can trigger crashes in critical processes responsible for packet forwarding, affecting device performance and stability.

Technical Details of CVE-2021-20657

This vulnerability affects Junos OS versions 14.1X53 to 19.4R2 on various Juniper Networks devices like EX Series, QFX Series, SRX Branch Series, and MX Series.

Vulnerability Description

A memory leak occurs on Junos OS devices each time the 802.1X authenticator port interface flaps, potentially causing crashes in processes like pfex.

Affected Systems and Versions

Devices running Junos OS versions prior to 12.3 and after 15.1 are unaffected. However, versions between 14.1X53 and 19.4R2 are prone to this issue.

Exploitation Mechanism

There are no known instances of malicious exploitation of this vulnerability according to Juniper SIRT.

Mitigation and Prevention

It is crucial to apply the provided software updates to secure affected Junos OS devices.

Immediate Steps to Take

Monitor memory consumption using the CLI command

show task memory detail

and apply the necessary patches immediately.

Long-Term Security Practices

Regularly update Junos OS software and follow best security practices to prevent memory leak vulnerabilities.

Patching and Updates

Juniper Networks has released updated software versions from 14.1X53-D54 to 20.1R1 to address this memory leak vulnerability.