CVE-2026-102066 Juniper Networks CVE debrief

Who should care

Network administrators and security teams responsible for managing Junos OS and Junos OS Evolved devices should assess exposure and prioritize patching or mitigation. They should also verify RSVP is not enabled on untrusted interfaces and monitor network interfaces for suspicious RSVP packets. Additionally, they should review and apply patches or updates for Junos OS and Junos OS Evolved, and plan vendor-supported updates or mitigations through normal

Why it matters

CVE-2026-102066 is a medium-severity vulnerability in Junos OS and Junos OS Evolved that could allow an adjacent unauthenticated attacker to cause a denial of service. Network administrators and security teams should assess exposure, prioritize patching or mitigation, and monitor network interfaces for suspicious activity.

• Potential denial-of-service attacks via malformed RSVP packets
• Need to verify RSVP is not enabled on untrusted interfaces
• Requirement to review and apply patches or updates for Junos OS and Junos OS Evolved
• Importance of monitoring network interfaces for suspicious RSVP packets

Technical summary

A vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent unauthenticated attacker to cause a denial of service via a malformed RSVP packet when RSVP is enabled on the receiving interface. The vulnerability is caused by improper validation of specified quantity in input, allowing an attacker to exploit this issue. The vulnerability has a CVSS score of 6.5, indicating a medium-severity issue. Network administrators and security teams should assess exposure and prioritize patching or mitigation.

Defensive priority

Network administrators should prioritize patching or mitigating this vulnerability to prevent potential denial-of-service attacks.

Recommended defensive actions

• Review and apply patches or updates for Junos OS and Junos OS Evolved
• Verify RSVP is not enabled on untrusted interfaces
• Monitor network interfaces for suspicious RSVP packets
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record and source item provide details on the vulnerability, including its description, affected versions, and potential impact. The vulnerability is caused by improper validation of specified quantity in input, allowing an adjacent unauthenticated attacker to cause a denial of service. The source item and CVE record provide additional information on the vulnerability, including its CVSS score and affected products.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.