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2020-04 Security Bulletin: Junos OS: A crafted Ethernet OAM packet received by Junos may cause the Ethernet OAM connectivity fault management process (CFM) to core. (CVE-2020-1639)



Article ID: JSA11020 SECURITY_ADVISORIES Last Updated: 08 Apr 2020Version: 1.0
Product Affected:
This issue affects Junos OS 12.3, 12.3X48, 14.1X50, 14.1X53, 15.1, 15.1X49, 15.1X53.

When an attacker sends a specific crafted Ethernet Operation, Administration, and Maintenance (Ethernet OAM) packet to a target device, it may improperly handle the incoming malformed data and fail to sanitize this incoming data resulting in an overflow condition. This overflow condition in Juniper Networks Junos OS allows an attacker to cause a Denial of Service (DoS) condition by coring the CFM daemon.

Continued receipt of these packets may cause an extended Denial of Service condition.

This issue affects:

Juniper Networks Junos OS

12.3 versions prior to 12.3R12-S15;

12.3X48 versions prior to 12.3X48-D95;

14.1X50 versions prior to 14.1X50-D145;

14.1X53 versions prior to 14.1X53-D47;

15.1 versions prior to 15.1R2;

15.1X49 versions prior to 15.1X49-D170;

15.1X53 versions prior to 15.1X53-D67.

This issue affects Junos OS devices with OAM Ethernet configured:

[protocols oam ethernet connectivity-fault-management]

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-2020-1639.


The following software releases have been updated to resolve this specific issue: 12.3R12-S15, 12.3X48-D95, 14.1X50-D145, 14.1X53-D47, 15.1R2, 15.1X49-D170, 16.1R1, and all subsequent releases.

This issue is being tracked as 999503.

There are no viable workarounds for this issue.
Software release Service Packages are available at from the "Download Software" links.
Modification History:
2020-04-08: Initial publication
CVSS Score:
7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
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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