CVE-2021-0250

Junos OS and Junos OS Evolved: An attacker sending a specific crafted BGP update message will crash RPD

Description

In segment routing traffic engineering (SRTE) environments where the BGP Monitoring Protocol (BMP) feature is enable, a vulnerability in the Routing Protocol Daemon (RPD) process of Juniper Networks Junos OS allows an attacker to send a specific crafted BGP update message causing the RPD service to core, creating a Denial of Service (DoS) Condition. Continued receipt and processing of this update message will create a sustained Denial of Service (DoS) condition. This issue affects IPv4 and IPv6 environments. This issue affects: Juniper Networks Junos OS 17.4 versions 17.4R1 and above prior to 17.4R2-S6, 17.4R3; 18.1 versions prior to 18.1R3-S7; 18.2 versions prior to 18.2R2-S6, 18.2R3-S3; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2-S3, 18.4R3; 19.1 versions prior to 19.1R1-S4, 19.1R2; 19.2 versions prior to 19.2R1-S3, 19.2R2, This issue does not affect Junos OS releases prior to 17.4R1. This issue affects: Juniper Networks Junos OS Evolved 19.2-EVO versions prior to 19.2R2-EVO.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS: 17.4R2-S6, 17.4R3, 18.1R3-S7, 18.2R2-S6, 18.2R3-S3, 18.3R1-S7, 18.3R2-S3, 18.3R3, 18.4R1-S5, 18.4R2-S3, 18.4R3, 19.1R1-S4, 19.1R2, 19.2R1-S3, 19.2R2, 19.3R1, and all subsequent releases. Junos OS Evolved: 19.2R2-EVO, and all subsequent releases.

Workaround:

  • Disable BGP monitoring protocol until a fix can be applied.
7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.39%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS Evolved
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11143 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0250?
CVE-2021-0250 has been scored as a high severity vulnerability.
How to fix CVE-2021-0250?
To fix CVE-2021-0250: The following software releases have been updated to resolve this specific issue: Junos OS: 17.4R2-S6, 17.4R3, 18.1R3-S7, 18.2R2-S6, 18.2R3-S3, 18.3R1-S7, 18.3R2-S3, 18.3R3, 18.4R1-S5, 18.4R2-S3, 18.4R3, 19.1R1-S4, 19.1R2, 19.2R1-S3, 19.2R2, 19.3R1, and all subsequent releases. Junos OS Evolved: 19.2R2-EVO, and all subsequent releases.
Is CVE-2021-0250 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0250 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-0250?
CVE-2021-0250 affects Juniper Networks Junos OS, Juniper Networks Junos OS Evolved.
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