CVE-2026-101975 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 updating affected versions to prevent potential network instability due to rpd crashes. They should also review OSPF configurations, apply vendor-provided patches, and monitor network traffic for suspicious OSPF activity.

Why it matters

CVE-2026-101975 is a medium-severity vulnerability in Junos OS and Junos OS Evolved that can cause a denial of service via OSPF traffic. Network administrators and security teams should prioritize verifying OSPF configurations and updating affected versions to prevent potential network instability.

• Denial of service via OSPF traffic
• Potential network instability due to rpd crashes
• Need for verification of OSPF configurations and affected versions
• Priority for applying vendor-provided patches

Technical summary

A Reachable Assertion vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent OSPF peer to cause a denial of service via OSPF traffic processed while OSPF Source Packet Routing best-route Prefix-SID installation is configured. The vulnerability can cause a denial of service and potential network instability due to rpd crashes. Network administrators and security teams should prioritize verifying OSPF configurations and updating affected versions to prevent potential network instability.

Defensive priority

Network administrators and security teams should prioritize verifying OSPF configurations and updating affected Junos OS and Junos OS Evolved versions.

Recommended defensive actions

• Verify OSPF configurations and update affected Junos OS and Junos OS Evolved versions
• Review and apply vendor-provided patches
• Monitor network traffic for suspicious OSPF activity
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record and source item provide details on the vulnerability in Junos OS and Junos OS Evolved. Specific details on exploitation are limited. Defenders should verify OSPF configurations, review vendor-provided patches, and monitor network traffic for suspicious OSPF activity. The source item and CVE record provide additional information on the vulnerability.

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.