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2021-10 Security Bulletin: Junos OS Evolved: BGP and LDP sessions with TCP MD5 authentication established with peers not configured for authentication (CVE-2021-0297)



Article ID: JSA11211 SECURITY_ADVISORIES Last Updated: 13 Oct 2021Version: 1.0
Product Affected:
This issue affects all versions of Junos OS Evolved.

A vulnerability in the processing of TCP MD5 authentication in Juniper Networks Junos OS Evolved may allow a BGP or LDP session configured with MD5 authentication to succeed, even if the peer does not have TCP MD5 authentication enabled. This could lead to untrusted or unauthorized sessions being established, resulting in an impact on confidentiality or stability of the network.

This issue affects Juniper Networks Junos OS Evolved:

  • All versions prior to 20.3R2-S1-EVO;
  • 20.4 versions prior to 20.4R2-EVO;
  • 21.1 versions prior to 21.1R2-EVO.

Juniper Networks Junos OS is not affected by this issue.

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

This issue was found during internal product security testing or research.

This issue has been assigned CVE-2021-0297.


The following software releases have been updated to resolve this specific issue: Junos OS Evolved 20.3R2-S1-EVO, 20.4R2-EVO, 21.1R2-EVO, 21.2R1-EVO, and all subsequent releases.

This issue is being tracked as 1569843.

There are no known workarounds for this issue.

Software releases or updates are available for download at
Modification History:
2021-10-13: Initial Publication.

CVSS Score:
6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N)
Severity Level:
Severity Assessment:
Information for how Juniper Networks uses CVSS can be found at KB 16446 "Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories."

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