CVE-2024-21596

Junos OS and Junos OS Evolved: A specific BGP UPDATE message will cause a crash in the backup Routing Engine in NSR-enabled devices

Description

A Heap-based Buffer Overflow vulnerability in the Routing Protocol Daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, network based attacker to cause a Denial of Service (DoS). If an attacker sends a specific BGP UPDATE message to the device, this will cause a memory overwrite and therefore an RPD crash and restart in the backup Routing Engine (RE). Continued receipt of these packets will cause a sustained Denial of Service (DoS) condition in the backup RE. The primary RE is not impacted by this issue and there is no impact on traffic. This issue only affects devices with NSR enabled. Note: NSR is not supported on the SRX Series and is therefore not affected by this vulnerability. This issue requires an attacker to have an established BGP session to a system affected by the issue. This issue affects both eBGP and iBGP implementations. This issue affects: Juniper Networks Junos OS * All versions earlier than 20.4R3-S9; * 21.2 versions earlier than 21.2R3-S7; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3-S5; * 22.1 versions earlier than 22.1R3-S4; * 22.2 versions earlier than 22.2R3-S2; * 22.3 versions earlier than 22.3R3-S1; * 22.4 versions earlier than 22.4R2-S2, 22.4R3; * 23.1 versions earlier than 23.1R2; * 23.2 versions earlier than 23.2R1-S2, 23.2R2. Juniper Networks Junos OS Evolved * All versions earlier than 21.3R3-S5-EVO; * 21.4-EVO versions earlier than 21.4R3-S5-EVO; * 22.1-EVO versions earlier than 22.1R3-S4-EVO; * 22.2-EVO versions earlier than 22.2R3-S2-EVO; * 22.3-EVO versions later than 22.3R1-EVO; * 22.4-EVO versions earlier than 22.4R2-S2-EVO, 22.4R3-EVO; * 23.1-EVO versions earlier than 23.1R2-EVO; * 23.2-EVO versions earlier than 23.2R1-S2-EVO, 23.2R2-EVO.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS: 21.2R3-S7, 21.3R3-S5, 21.4R3-S5, 22.1R3-S4, 22.2R3-S2, 22.3R3-S1, 22.4R2-S2, 22.4R3, 23.1R2, 23.2R1-S2, 23.2R2, 23.3R1, 23.4R1, and all subsequent releases. Junos OS Evolved: 21.3R3-S5-EVO, 21.4R3-S5-EVO, 22.1R3-S4-EVO, 22.2R3-S2-EVO, 22.4R2-S2-EVO, 22.4R3-EVO, 23.1R2-EVO, 23.2R1-S2-EVO, 23.2R2-EVO, 23.3R1-EVO, 23.4R1-EVO, and all subsequent releases.

Workaround:

  • There are no known workarounds for this issue.

Categories

5.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.07%
Vendor Advisory juniper.net Vendor Advisory first.org
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS Evolved
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2024-21596?
CVE-2024-21596 has been scored as a medium severity vulnerability.
How to fix CVE-2024-21596?
To fix CVE-2024-21596: The following software releases have been updated to resolve this specific issue: Junos OS: 21.2R3-S7, 21.3R3-S5, 21.4R3-S5, 22.1R3-S4, 22.2R3-S2, 22.3R3-S1, 22.4R2-S2, 22.4R3, 23.1R2, 23.2R1-S2, 23.2R2, 23.3R1, 23.4R1, and all subsequent releases. Junos OS Evolved: 21.3R3-S5-EVO, 21.4R3-S5-EVO, 22.1R3-S4-EVO, 22.2R3-S2-EVO, 22.4R2-S2-EVO, 22.4R3-EVO, 23.1R2-EVO, 23.2R1-S2-EVO, 23.2R2-EVO, 23.3R1-EVO, 23.4R1-EVO, and all subsequent releases.
Is CVE-2024-21596 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-21596 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-2024-21596?
CVE-2024-21596 affects Juniper Networks Junos OS, Juniper Networks Junos OS Evolved.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.