CVE-2026-21902: Junos OS Evolved: PTX Series: A vulnerability allows a unauthenticated, network-based attacker to execute code as root
An Incorrect Permission Assignment for Critical Resource vulnerability in the On-Box Anomaly detection framework of Juniper Networks Junos OS Evolved on PTX Series allows an unauthenticated, network-based attacker to execute code as root.
The On-Box Anomaly detection framework should only be reachable by other internal processes over the internal routing instance, but not over an externally exposed port. With the ability to access and manipulate the service to execute code as root a remote attacker can take complete control of the device. Please note that this service is enabled by default as no specific configuration is required.
This issue affects Junos OS Evolved on PTX Series:
25.4 versions before 25.4R1-S1-EVO, 25.4R2-EVO.
This issue does not affect Junos OS Evolved versions before 25.4R1-EVO.
This issue does not affect Junos OS.
Affected Software
Remediation
Information
Event History
Frequently Asked Questions
What is the severity of CVE-2026-21902?
CVE-2026-21902 is classified as a critical vulnerability allowing unauthenticated network-based root code execution.
How do I fix CVE-2026-21902?
To remedy CVE-2026-21902, update Junos OS Evolved to a version beyond 25.4R2-EVO.
Which products are affected by CVE-2026-21902?
CVE-2026-21902 affects Juniper Networks' Junos OS Evolved specifically on PTX Series devices.
Can CVE-2026-21902 be exploited remotely?
Yes, CVE-2026-21902 can be exploited by an unauthenticated, network-based attacker.
What type of vulnerability is CVE-2026-21902?
CVE-2026-21902 is characterized as an Incorrect Permission Assignment for Critical Resource vulnerability.