CVE-2024-21599

Junos OS: MX Series: MPC3E memory leak with PTP configuration

Description

A Missing Release of Memory after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX Series allows an adjacent, unauthenticated attacker to cause a Denial of Service (DoS). If an MX Series device receives PTP packets on an MPC3E that doesn't support PTP this causes a memory leak which will result in unpredictable behavior and ultimately in an MPC crash and restart. To monitor for this issue, please use the following FPC vty level commands: show heap shows an increase in "LAN buffer" utilization and show clksync ptp nbr-upd-info shows non-zero "Pending PFEs" counter. This issue affects Juniper Networks Junos OS on MX Series with MPC3E: * All versions earlier than 20.4R3-S3; * 21.1 versions earlier than 21.1R3-S4; * 21.2 versions earlier than 21.2R3; * 21.3 versions earlier than 21.3R2-S1, 21.3R3; * 21.4 versions earlier than 21.4R2; * 22.1 versions earlier than 22.1R2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S3, 21.1R3-S4, 21.2R3, 21.3R2-S1, 21.3R3, 21.4R2, 22.1R2, 22.2R1, and all subsequent releases.

Workaround:

  • Although not a workaround the leaked memory can be recovered by: deactivate protocol ptp; commit; activate protocol ptp; commit.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.05%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://supportportal.juniper.net/JSA75740 vendor advisory
https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L third party advisory technical description

Frequently Asked Questions

What is the severity of CVE-2024-21599?
CVE-2024-21599 has been scored as a medium severity vulnerability.
How to fix CVE-2024-21599?
To fix CVE-2024-21599: The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S3, 21.1R3-S4, 21.2R3, 21.3R2-S1, 21.3R3, 21.4R2, 22.1R2, 22.2R1, and all subsequent releases.
Is CVE-2024-21599 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-21599 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-2024-21599?
CVE-2024-21599 affects Juniper Networks Junos OS.
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.