Vulnerability · Published Feb 25, 2026 · Assigned by juniper
CVE-2026-21902Junos OS Evolved: PTX Series: A vulnerability allows a unauthenticated, network-based attacker to execute code as root
Critical 9.8
In plain English
A critical-severity incorrect permission assignment in Junos OS Evolved from Juniper Networks. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 18.5% (higher than 97% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.
Official description
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 products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Juniper Networks | Junos OS Evolved | 25.4 – before 25.4R1-S1-EVO, 25.4R2-EVO |
Weakness: CWE-732 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H