CVE-2026-21913An 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 D…

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.

CVSS

7.5 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness (CWE)

CWE-665

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

Not given

NVD analysis

Analyzed

Record last updated

Jun 17, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.