CVE-2026-21913

published 2026-01-15

CVE-2026-21913: An Incorrect Initialization of Resource vulnerability in the Internal Device Manager (IDM) of Juniper Networks Junos OS on EX4000 models allows an…

Priority P3 46 high 7.5 CVSS 3.1

AV N AC L PR N UI N S U C N I N A H

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

5 ranges

Vendor	Product	Version range	Fixed in
juniper	junos	—	—
juniper	junos	—	—
juniper	junos_os	—	—
juniper_networks	junos_os	>= 24.4 < 24.4R2	24.4R2
juniper_networks	junos_os	>= 25.2 < 25.2R1-S2, 25.2R2	25.2R1-S2, 25.2R2

CVSS provenance

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

nvd v4.0 8.7 HIGH CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:A/V:X/RE:M/U:X

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