CVE-2021-0282: On Juniper Networks Junos OS devices with Multipath or add-path feature enabled, processing a specific BGP UPDATE can lead to a routing process daemon...

Description

On Juniper Networks Junos OS devices with Multipath or add-path feature enabled, processing a specific BGP UPDATE can lead to a routing process daemon (RPD) crash and restart, causing a Denial of Service (DoS). Continued receipt and processing of this UPDATE message will create a sustained Denial of Service (DoS) condition. This BGP UPDATE message can propagate to other BGP peers with vulnerable Junos versions on which Multipath or add-path feature is enabled, and cause RPD to crash and restart. This issue affects both IBGP and EBGP deployments in IPv4 or IPv6 network. Junos OS devices that do not have the BGP Multipath or add-path feature enabled are not affected by this issue. This issue affects: Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S18; 15.1 versions prior to 15.1R7-S9; 17.3 versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R2-S13, 17.4R3-S4; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R3-S7; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R2-S6, 18.4R3-S6; 19.1 versions prior to 19.1R3-S3;

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

0.95%

56.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions	Update
Juniper	Junos	12.3	—
Juniper	Junos	15.1	—
Juniper	Junos	17.3	—
Juniper	Junos	17.4	R2-S2
Juniper	Junos	18.1	—
Juniper	Junos	18.2	—
Juniper	Junos	18.3	—
Juniper	Junos	18.4	—
Juniper	Junos	19.1	—

References

https://kb.juniper.net/JSA11186Vendor Advisory
https://kb.juniper.net/JSA11186Vendor Advisory

Timeline

Published: Jul 15, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-0282?

On Juniper Networks Junos OS devices with Multipath or add-path feature enabled, processing a specific BGP UPDATE can lead to a routing process daemon (RPD) crash and restart, causing a Denial of Service (DoS). Continued receipt and processing of this UPDATE message will create a sustained Denial of Service (DoS) condition. This BGP UPDATE message can propagate to other BGP peers with vulnerable Junos versions on which Multipath or add-path feature is enabled, and cause RPD to crash and restart. This issue affects both IBGP and EBGP deployments in IPv4 or IPv6 network. Junos OS devices that do not have the BGP Multipath or add-path feature enabled are not affected by this issue. This issue affects: Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S18; 15.1 versions prior to 15.1R7-S9; 17.3 versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R2-S13, 17.4R3-S4; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R3-S7; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R2-S6, 18.4R3-S6; 19.1 versions prior to 19.1R3-S3;

How severe is CVE-2021-0282?

CVE-2021-0282 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.95% probability of exploitation in the next 30 days.

How do I fix CVE-2021-0282?

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.