CVE-2026-21902
9.8 · CRITICALOverview
CVE-2026-21902 is a critical-severity vulnerability affecting juniper junos_os_evolved. It was published on February 25, 2026 and has a CVSS 3.1 base score of 9.8 (CRITICAL).
This vulnerability has a CVSS 3.1 base score of 9.8, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from juniper. Update junos_os_evolved to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|
Frequently Asked Questions
What is CVE-2026-21902?
CVE-2026-21902 is a critical-severity vulnerability affecting juniper junos_os_evolved. It was published on February 25, 2026 and has a CVSS 3.1 base score of 9.8 (CRITICAL).
How severe is CVE-2026-21902?
This vulnerability has a CVSS 3.1 base score of 9.8, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-21902?
Check the references section for vendor advisories and patches from juniper. Update junos_os_evolved to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-21902?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-21902 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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