CVE-2026-102087 Juniper Networks CVE debrief

Who should care

Network administrators and security teams responsible for managing and securing Juniper Networks Junos OS and Junos OS Evolved devices should be aware of this vulnerability and take necessary actions to prevent potential DoS attacks.

Why it matters

A Denial-of-Service (DoS) vulnerability exists in Juniper Networks Junos OS and Junos OS Evolved, which can be exploited by an unauthenticated, adjacent attacker. Network administrators and security teams should be aware of this vulnerability and take necessary actions to prevent potential DoS attacks.

• Potential traffic impact until routing has reconverged
• Need to verify and update to fixed versions of Junos OS and Junos OS Evolved
• Possible DoS attacks if not properly mitigated

Technical summary

The vulnerability exists in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved. An unauthenticated, adjacent attacker can cause a Denial-of-Service (DoS) by sending a specific, valid, optional, non-transitive BGP update over an established BGP session in a BGP traffic engineering scenario. This leads to traffic impact until routing has reconverged. The affected versions of Junos OS and Junos OS Evolved are: Junos OS: * All versions before 23.2R2-S6; * 23.4 versions before 23.4R2-S7; * 24.2 versions before 24.2R2-S4; * 24.4 versions before 24.4R2-S4; * 25.2 versions before 25.2R1-S2, 25.2R2; Junos OS Evolved: * All versions before 23.2R2-S6-EVO; * 23.4 versions before 23.4R2-S8.1

Defensive priority

Network administrators should prioritize verifying and updating to the fixed versions of Junos OS and Junos OS Evolved to prevent potential DoS attacks.

Recommended defensive actions

• Verify and update to the fixed versions of Junos OS and Junos OS Evolved
• Monitor BGP sessions for suspicious activity
• Implement network segmentation to limit the impact of a potential DoS attack
• 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
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and source item provide details on the vulnerability, including its impact and affected versions of Junos OS and Junos OS Evolved. The vulnerability exists in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved. An unauthenticated, adjacent attacker can cause a Denial-of-Service (DoS) by sending a specific, valid, optional, non-transitive BGP update over an established BGP session in a BGP traffic engineering scenario. This leads to traffic impact until routing has reconverged. Network A

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.