CVE-2026-21902

High PUBLISHED

Junos OS Evolved: PTX Series: A vulnerability allows a unauthenticated, network-based attacker to execute code as root

Juniper Networks · Junos OS Evolved

Not yet in CISA KEV

Exploited in the wild PoC available

Recommended Action

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Confidence
High
Exploitation Status
Exploited in the wild
Observed in Sensors
No
Attempts (30d)
Unique Attacker IPs
CISA KEV
Not yet in CISA KEV
CVSS / EPSS
9.3 Critical

At a Glance

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.

CVE Published
Feb 25, 2026
Exploitation Reported
Mar 19, 2026
CVSS
9.3 Critical
EPSS
Remote Low complexity No user interaction Unauthenticated

Affected Versions

Vendor Product Version Status
Juniper Networks
Junos OS Evolved

25.4 to < 25.4R1-S1-EVO, 25.4R2-EVO

Affected
Juniper Networks
Junos OS Evolved

0 to < 25.4R1-EVO

Unaffected

CVE References

Recommended Actions

  • Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
  • Check enrichment artifacts for scanner coverage and available PoCs before rolling remediation validation.
  • Use the Pro API to automate enrichment, telemetry, and workflow delivery for VM, SOC, and CTI pipelines.