CVE-2024-21617: Junos OS: BGP flap on NSR-enabled devices causes memory leak

Published Jan 12, 2024
·
Updated

An Incomplete Cleanup vulnerability in Nonstop active routing (NSR) component of Juniper Networks Junos OS allows an adjacent, unauthenticated attacker to cause memory leak leading to Denial of Service (DoS).

On all Junos OS platforms, when NSR is enabled, a BGP flap will cause memory leak. A manual reboot of the system will restore the services.

Note: NSR is not supported on the SRX Series and is therefore not affected by this vulnerability. The memory usage can be monitored using the below commands.

user@host> show chassis routing-engine no-forwarding user@host> show system memory | no-more This issue affects:

Juniper Networks Junos OS

21.2 versions earlier than 21.2R3-S5; 21.3 versions earlier than 21.3R3-S4; 21.4 versions earlier than 21.4R3-S4; 22.1 versions earlier than 22.1R3-S2; 22.2 versions earlier than 22.2R3-S2; 22.3 versions earlier than 22.3R2-S1, 22.3R3; 22.4 versions earlier than 22.4R1-S2, 22.4R2.

This issue does not affect Junos OS versions earlier than 20.4R3-S7.

Affected Software

60 affected components
Juniper Junos=21.2
Juniper Junos=21.2-r1
Juniper Junos=21.2-r1-s1
Juniper Junos=21.2-r1-s2
Juniper Junos=21.2-r2
Juniper Junos=21.2-r2-s1
Juniper Junos=21.2-r2-s2
Juniper Junos=21.2-r3
Juniper Junos=21.2-r3-s1
Juniper Junos=21.2-r3-s2
Juniper Junos=21.2-r3-s3
Juniper Junos=21.2-r3-s4
Juniper Junos=21.3
Juniper Junos=21.3-r1
Juniper Junos=21.3-r1-s1
Juniper Junos=21.3-r1-s2
Juniper Junos=21.3-r2
Juniper Junos=21.3-r2-s1
Juniper Junos=21.3-r2-s2
Juniper Junos=21.3-r3
Juniper Junos=21.3-r3-s1
Juniper Junos=21.3-r3-s2
Juniper Junos=21.3-r3-s3
Juniper Junos=21.4
Juniper Junos=21.4-r1
Juniper Junos=21.4-r1-s1
Juniper Junos=21.4-r1-s2
Juniper Junos=21.4-r2
Juniper Junos=21.4-r2-s1
Juniper Junos=21.4-r2-s2
Juniper Junos=21.4-r3
Juniper Junos=21.4-r3-s1
Juniper Junos=21.4-r3-s2
Juniper Junos=21.4-r3-s3
Juniper Junos=22.1
Juniper Junos=22.1-r1
Juniper Junos=22.1-r1-s1
Juniper Junos=22.1-r1-s2
Juniper Junos=22.1-r2
Juniper Junos=22.1-r2-s1
Juniper Junos=22.1-r2-s2
Juniper Junos=22.1-r3
Juniper Junos=22.1-r3-s1
Juniper Junos=22.2
Juniper Junos=22.2-r1
Juniper Junos=22.2-r1-s1
Juniper Junos=22.2-r1-s2
Juniper Junos=22.2-r2
Juniper Junos=22.2-r2-s1
Juniper Junos=22.2-r2-s2
Juniper Junos=22.2-r3
Juniper Junos=22.2-r3-s1
Juniper Junos=22.3
Juniper Junos=22.3-r1
Juniper Junos=22.3-r1-s1
Juniper Junos=22.3-r1-s2
Juniper Junos=22.3-r2
Juniper Junos=22.4
Juniper Junos=22.4-r1
Juniper Junos=22.4-r1-s1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Juniper Networks Junos OS to a version that resolves this vulnerability.

    Fixed in 21.2R3-S5
  2. Upgrade

    Upgrade Juniper Networks Junos OS to a version that resolves this vulnerability.

    Fixed in 21.3R3-S4
  3. Upgrade

    Upgrade Juniper Networks Junos OS to a version that resolves this vulnerability.

    Fixed in 21.4R3-S4
  4. Upgrade

    Upgrade Juniper Networks Junos OS to a version that resolves this vulnerability.

    Fixed in 22.1R3-S2
  5. Upgrade

    Upgrade Juniper Networks Junos OS to a version that resolves this vulnerability.

    Fixed in 22.2R3-S2
  6. Upgrade

    Upgrade Juniper Networks Junos OS to a version that resolves this vulnerability.

    Fixed in 22.3R2-S1
  7. Upgrade

    Upgrade Juniper Networks Junos OS to a version that resolves this vulnerability.

    Fixed in 22.3R3
  8. Upgrade

    Upgrade Juniper Networks Junos OS to a version that resolves this vulnerability.

    Fixed in 22.4R1-S2
  9. Upgrade

    Upgrade Juniper Networks Junos OS to a version that resolves this vulnerability.

    Fixed in 22.4R2
  10. Upgrade

    Upgrade Juniper Networks Junos OS to a version that resolves this vulnerability.

    Fixed in 23.2R1
  11. Compensating control

    On NSR-enabled Junos OS devices, avoid BGP flaps while running a release that is earlier than the updated fixed releases; NSR is not supported on the SRX Series and is therefore not affected by this vulnerability.

  12. Operational

    After occurrence/mitigation, perform a manual reboot of the system to restore the services.

  13. Operational

    Monitor memory usage on the routing engine using: 'show chassis routing-engine no-forwarding' and 'show system memory | no-more'.

Event History

Jan 12, 2024
CVE Published
via MITRE·12:57 AM
Data Sourced
via MITRE·12:57 AM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·01:15 AM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2024-21617?

CVE-2024-21617 is classified as having a high severity due to its ability to cause a Denial of Service (DoS).

2

How do I fix CVE-2024-21617?

To mitigate CVE-2024-21617, upgrade to the latest patched version of Junos OS as recommended by Juniper Networks.

3

Which versions of Junos OS are affected by CVE-2024-21617?

CVE-2024-21617 affects multiple versions of Junos OS, including 21.2, 21.3, 21.4, 22.1, 22.2, and 22.3.

4

Can CVE-2024-21617 be exploited remotely?

Yes, CVE-2024-21617 can be exploited by an adjacent, unauthenticated attacker.

5

What impact does CVE-2024-21617 have on system performance?

CVE-2024-21617 can lead to a memory leak which significantly degrades system performance and may cause a Denial of Service.

Contact

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