On Juniper Networks Junos OS Evolved devices, receipt of a specific IPv6 packet may cause an established IPv6 BGP session to terminate, creating a Denial of Service (DoS) condition.

Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition.

This issue does not affect IPv4 BGP sessions.

This issue affects IBGP or EBGP peer sessions with IPv6.

This issue affects:

Juniper Networks Junos OS Evolved:

• 19.4 versions prior to 19.4R2-S3-EVO;
• 20.1 versions prior to 20.1R2-S3-EVO;
• 20.2 versions prior to 20.2R2-S1-EVO;
• 20.3 versions prior to 20.3R2-EVO.

This issue does not affect Juniper Networks Junos OS releases.

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

This issue was seen during production usage.

This issue has been assigned CVE-2021-0226 .

The following software releases have been updated to resolve this specific issue: Junos OS Evolved: 19.4R2-S3-EVO, 20.1R2-S3-EVO, 20.2R2-S1-EVO, 20.3R2-EVO, 20.4R1-EVO, and all subsequent releases.

This issue is being tracked as 1544978 .

Software releases or updates are available for download at https://support.juniper.net/support/downloads/

There are no viable workarounds for this issue.

2021-04-14: Initial Publication.

• KB16613: Overview of the Juniper Networks SIRT Quarterly Security Bulletin Publication Process [juniper.net]
• KB16765: In which releases are vulnerabilities fixed? [juniper.net]
• KB16446: Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories [juniper.net]
• Report a Security Vulnerability - How to Contact the Juniper Networks Security Incident Response Team
• CVE-2021-0226 at cve.mitre.org