Description
An Incorrect Initialization of Resource vulnerability in the Internal Device Manager (IDM) of Juniper Networks Junos OS on EX4000 models allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).
On EX4000 models with 48 ports (EX4000-48T, EX4000-48P, EX4000-48MP) a high volume of traffic destined to the device will cause an FXPC crash and restart, which leads to a complete service outage until the device has automatically restarted.
The following reboot reason can be seen in the output of 'show chassis routing-engine' and as a log message:
reason=0x4000002 reason_string=0x4000002:watchdog + panic with core dump
This issue affects Junos OS on EX4000-48T, EX4000-48P and EX4000-48MP:
* 24.4 versions before 24.4R2,
* 25.2 versions before 25.2R1-S2, 25.2R2.
This issue does not affect versions before 24.4R1 as the first Junos OS version for the EX4000 models was 24.4R1.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Juniper Networks | Junos OS | 24.4 – < 24.4R2, 25.2 – < 25.2R1-S2, 25.2R2 | 24.4R2 |
Advisories 2
- NCSC-2026-0017 Kwetsbaarheden verholpen in Juniper Networks JunOS NCSC-NL (Netherlands) · Jan 16, 2026
- WID-SEC-2026-0117 Juniper Junos OS, Junos Space: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jan 15, 2026
References
- https://supportportal.juniper.net/JSA106014 vendor-advisory
- https://kb.juniper.net/JSA106014 vendor-advisory