CVE-2020-1644: On Juniper Networks Junos OS and Junos OS Evolved devices, the receipt of a specific BGP UPDATE packet causes an internal counter to be incremented in...

Description

On Juniper Networks Junos OS and Junos OS Evolved devices, the receipt of a specific BGP UPDATE packet causes an internal counter to be incremented incorrectly, which over time can lead to the routing protocols process (RPD) crash and restart. This issue affects both IBGP and EBGP multihop deployment in IPv4 or IPv6 network. This issue affects: Juniper Networks Junos OS: 17.2X75 versions prior to 17.2X75-D105.19; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S10, 17.4R3-S2; 18.1 versions prior to 18.1R3-S10; 18.2 versions prior to 18.2R2-S7, 18.2R3-S4; 18.2X75 versions prior to 18.2X75-D13, 18.2X75-D411.1, 18.2X75-D420.18, 18.2X75-D52.3, 18.2X75-D60; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2; 18.4 versions prior to 18.4R1-S7, 18.4R2-S4, 18.4R3-S2; 19.1 versions prior to 19.1R1-S5, 19.1R2-S1, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S2, 19.3R3; 19.4 versions prior to 19.4R1-S2, 19.4R2. Juniper Networks Junos OS Evolved: any releases prior to 20.1R2-EVO. This issue does not affect Juniper Networks Junos OS releases prior to 17.3R1.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

1.28%

66.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions	Update
Juniper	Junos	17.2x75	—
Juniper	Junos	17.3	—
Juniper	Junos	17.4	—
Juniper	Junos	18.1	—
Juniper	Junos	18.2	—
Juniper	Junos	18.2x75	—
Juniper	Junos	18.3	—
Juniper	Junos	18.4	—
Juniper	Junos	19.1	—
Juniper	Junos	19.2	—
Juniper	Junos	19.3	—
Juniper	Junos	19.4	R1
Juniper	Junos Os Evolved	18.3	R1
Juniper	Junos Os Evolved	19.1	R1
Juniper	Junos Os Evolved	19.2	R1
Juniper	Junos Os Evolved	19.3	R1
Juniper	Junos Os Evolved	20.1	R1

References

https://kb.juniper.net/JSA11032Vendor Advisory
https://kb.juniper.net/JSA11032Vendor Advisory

Timeline

Published: Jul 17, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-1644?

On Juniper Networks Junos OS and Junos OS Evolved devices, the receipt of a specific BGP UPDATE packet causes an internal counter to be incremented incorrectly, which over time can lead to the routing protocols process (RPD) crash and restart. This issue affects both IBGP and EBGP multihop deployment in IPv4 or IPv6 network. This issue affects: Juniper Networks Junos OS: 17.2X75 versions prior to 17.2X75-D105.19; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S10, 17.4R3-S2; 18.1 versions prior to 18.1R3-S10; 18.2 versions prior to 18.2R2-S7, 18.2R3-S4; 18.2X75 versions prior to 18.2X75-D13, 18.2X75-D411.1, 18.2X75-D420.18, 18.2X75-D52.3, 18.2X75-D60; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2; 18.4 versions prior to 18.4R1-S7, 18.4R2-S4, 18.4R3-S2; 19.1 versions prior to 19.1R1-S5, 19.1R2-S1, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S2, 19.3R3; 19.4 versions prior to 19.4R1-S2, 19.4R2. Juniper Networks Junos OS Evolved: any releases prior to 20.1R2-EVO. This issue does not affect Juniper Networks Junos OS releases prior to 17.3R1.

How severe is CVE-2020-1644?

CVE-2020-1644 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.28% probability of exploitation in the next 30 days.

How do I fix CVE-2020-1644?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.