Product:
Junos OS
Summary
An Incorrect Initialization of Resource vulnerability in the Internal Device Manager of Junos OS on EX4000 models allows an unauthenticated, network-based attacker to cause a Denial-of-Service. A high volume of traffic destined to the device will cause an FXPC crash and restart, leading to a complete service outage until the device has automatically restarted. This issue affects specific EX4000 models running certain versions of Junos OS.
Details
| Severity | Base Score | CVE |
|---|---|---|
| HIGH | 8.7 | CVE-2026-21913 |
Exploitation
To exploit this vulnerability, an attacker can send a high volume of traffic to the affected EX4000 models. This traffic overloads the device, causing it to crash and restart, resulting in a Denial-of-Service condition. The attacker does not need any authentication or special privileges to carry out this attack, making it relatively easy to execute.
Affected Products
- EX4000-48T: Affected by the vulnerability when running specific versions of Junos OS.
- EX4000-48P: Vulnerable under the same conditions as the EX4000-48T.
- EX4000-48MP: Also affected when running the specified versions of Junos OS.
Mitigation
To mitigate this vulnerability, it is recommended to upgrade the affected EX4000 models to the latest versions of Junos OS that are not impacted by this issue. Regular monitoring of network traffic and implementing rate limiting can also help prevent exploitation.