CVE Vulnerabilities


Missing Release of Memory after Effective Lifetime

Published: Jan 12, 2024 | Modified: Jan 19, 2024
CVSS 3.x
CVSS 2.x

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 doesnt 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.


The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory.

Affected Software

Name Vendor Start Version End Version
Junos Juniper 20.4 (including) 20.4 (including)
Junos Juniper 20.4-r1 (including) 20.4-r1 (including)
Junos Juniper 20.4-r1-s1 (including) 20.4-r1-s1 (including)
Junos Juniper 20.4-r2 (including) 20.4-r2 (including)
Junos Juniper 20.4-r2-s1 (including) 20.4-r2-s1 (including)
Junos Juniper 20.4-r2-s2 (including) 20.4-r2-s2 (including)
Junos Juniper 20.4-r3 (including) 20.4-r3 (including)
Junos Juniper 20.4-r3-s1 (including) 20.4-r3-s1 (including)
Junos Juniper 20.4-r3-s2 (including) 20.4-r3-s2 (including)

Potential Mitigations

  • Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.
  • For example, glibc in Linux provides protection against free of invalid pointers.
  • When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].
  • To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.