CVE-2025-30647: MX Series: Subscriber login/logout activity will lead to a memory leak

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 Series) 0	21.2R3-S9 or later
Junos OS (MX Series) 21.4	21.4R3-S10 or later
Junos OS (MX Series) 22.2	22.2R3-S6 or later
Junos OS (MX Series) 22.4	22.4R3-S5 or later
Junos OS (MX Series) 23.2	23.2R2-S3 or later
Junos OS (MX Series) 23.4	23.4R2-S3 or later
Junos OS (MX Series) 24.2	24.2R2 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 Juniper Networks Junos OS on MX Series allows an unauthenticated adjacent attacker to cause a Denial-of-Service (DoS).

In a subscriber management scenario, login/logout activity triggers a memory leak, and the leaked memory gradually increments and eventually results in a crash.

user@host> show chassis fpc Temp CPU Utilization (%) CPU Utilization (%) Memory Utilization (%) Slot State (C) Total Interrupt 1min 5min 15min DRAM (MB) Heap Buffer

2 Online 36 10 0 9 8 9 32768 26 0

This issue affects Junos OS on MX Series: * All versions before 21.2R3-S9 * from 21.4 before 21.4R3-S10 * from 22.2 before 22.2R3-S6 * from 22.4 before 22.4R3-S5 * from 23.2 before 23.2R2-S3 * from 23.4 before 23.4R2-S3 * from 24.2 before 24.2R2.

Am I affected?

To be exposed to this vulnerability subscriber management needs to be enabled via:

[system services subscriber-management enable]

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.