CVE-2026-21902

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://kb.juniper.net/JSA107128
https://supportportal.juniper.net/JSA107128
https://github.com/watchtowrlabs/watchTowr-vs-JunosEvolved-CVE-2026-21902/blob/main/watchTowr-vs-JunosEvolved-CVE-2026-21902.py

Configurations

No configuration.

History

03 Mar 2026, 15:16

Type	Values Removed	Values Added
References		() https://github.com/watchtowrlabs/watchTowr-vs-JunosEvolved-CVE-2026-21902/blob/main/watchTowr-vs-JunosEvolved-CVE-2026-21902.py -

25 Feb 2026, 18:23

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-25 18:23

Updated : 2026-03-03 15:16

NVD link : CVE-2026-21902

Mitre link : CVE-2026-21902

CVE.ORG link : CVE-2026-21902

JSON object : View

Products Affected

No product.

CWE

CWE-732

Incorrect Permission Assignment for Critical Resource

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