CVE-2023-36840

Junos OS and Junos OS Evolved: An rpd crash occurs when a specific L2VPN command is run

Description

A Reachable Assertion vulnerability in Routing Protocol Daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows a locally-based, low-privileged attacker to cause a Denial of Service (DoS). On all Junos OS and Junos OS Evolved, when a specific L2VPN command is run, RPD will crash and restart. Continued execution of this specific command will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS All versions prior to 19.3R3-S10; 20.1 versions prior to 20.1R3-S4; 20.2 versions prior to 20.2R3-S6; 20.3 versions prior to 20.3R3-S6; 20.4 versions prior to 20.4R3-S5; 21.1 versions prior to 21.1R3-S4; 21.2 versions prior to 21.2R3-S3; 21.3 versions prior to 21.3R3-S2; 21.4 versions prior to 21.4R3; 22.1 versions prior to 22.1R3; 22.2 versions prior to 22.2R2; 22.3 versions prior to 22.3R2; Juniper Networks Junos OS Evolved All versions prior to 20.4R3-S7-EVO; 21.1 versions prior to 21.1R3-S3-EVO; 21.2 versions prior to 21.2R3-S5-EVO; 21.3 versions prior to 21.3R3-S4-EVO; 21.4 versions prior to 21.4R3-EVO; 22.1 versions prior to 22.1R3-EVO; 22.2 versions prior to 22.2R2-EVO; 22.3 versions prior to 22.3R2-EVO;

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS: 19.3R3-S7, 19.4R3-S10, 20.2R3-S6, 20.4R3-S5, 21.1R3-S4, 21.2R3-S3, 21.3R3-S2, 21.4R3, 22.1R3, 22.2R2, 22.3R2, 22.4R1, and all subsequent releases; Junos OS Evolved: 20.4R3-S7-EVO, 21.4R3-EVO, 22.1R3-EVO, 22.2R2-EVO, 22.3R2-EVO, 22.4R1-EVO, and all subsequent releases.

Workaround:

  • This issue can be avoided by using access lists or firewall filters to limit access to the device to only trusted hosts, networks and administrators.

Category

5.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.07%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS Evolved
Published at:
Updated at:

References

Link Tags
https://supportportal.juniper.net/JSA71647 mitigation vendor advisory

Frequently Asked Questions

What is the severity of CVE-2023-36840?
CVE-2023-36840 has been scored as a medium severity vulnerability.
How to fix CVE-2023-36840?
To fix CVE-2023-36840: The following software releases have been updated to resolve this specific issue: Junos OS: 19.3R3-S7, 19.4R3-S10, 20.2R3-S6, 20.4R3-S5, 21.1R3-S4, 21.2R3-S3, 21.3R3-S2, 21.4R3, 22.1R3, 22.2R2, 22.3R2, 22.4R1, and all subsequent releases; Junos OS Evolved: 20.4R3-S7-EVO, 21.4R3-EVO, 22.1R3-EVO, 22.2R2-EVO, 22.3R2-EVO, 22.4R1-EVO, and all subsequent releases.
Is CVE-2023-36840 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-36840 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-2023-36840?
CVE-2023-36840 affects Juniper Networks Junos OS, Juniper Networks Junos OS Evolved.
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