CVE-2024-47493: MX Series: Trio-based FPCs: Continuous physical Interface flaps causes local FPC to crash

Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.

Affected and fixed versions

Product / branch	Fixed in
Junos OS (MX) 0	21.2R3-S7 or later
Junos OS (MX) 21.4	21.4R3-S6 or later
Junos OS (MX) 22.1	22.1R3-S5 or later
Junos OS (MX) 22.2	22.2R3-S3 or later
Junos OS (MX) 22.3	22.3R3-S2 or later
Junos OS (MX) 22.4	22.4R3 or later
Junos OS (MX) 23.2	23.2R2 or later
Junos OS (MX) 23.4	23.4R2 or later

Always confirm against the vendor advisory, which lists every fixed hotfix.

What it is

A Missing Release of Memory after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of the Juniper Networks Junos OS on the MX Series platforms with Trio-based FPCs allows an unauthenticated, adjacent attacker to cause a Denial of Service (DoS).

In case of channelized Modular Interface Cards (MICs), every physical interface flap operation will leak heap memory. Over a period of time, continuous physical interface flap operations causes local FPC to eventually run out of memory and crash.

Below CLI command can be used to check the memory usage over a period of time:

user@host> show chassis fpc

Temp CPU Utilization (%) CPU Utilization (%) Memory Utilization (%) Slot State (C) Total Interrupt 1min 5min 15min DRAM (MB) Heap Buffer

0 Online 43 41 2 2048 49 14

1 Online 43 41 2 2048 49 14

2 Online 43 41 2 2048 49 14

This issue affects Junos OS on MX Series:

All versions before 21.2R3-S7,
from 21.4 before 21.4R3-S6,
from 22.1 before 22.1R3-S5,
from 22.2 before 22.2R3-S3,
from 22.3 before 22.3R3-S2,
from 22.4 before 22.4R3,
from 23.2 before 23.2R2,
from 23.4 before 23.4R2.

Workarounds

There are no known workarounds for this issue.

Exploitation

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.