CVE-2026-101934 Juniper Networks CVE debrief

Who should care

System administrators and security teams responsible for Junos OS and Junos OS Evolved systems, especially those with versions prior to 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, and 26.2R1-S2. These teams should assess exposure, prioritize patching or mitigation, and verify system versions to prevent potential impact on network availability and reliability.

Why it matters

CVE-2026-101934 is a medium-severity vulnerability in Junos OS and Junos OS Evolved that can lead to Denial of Service (DoS) if exploited. System administrators and security teams should assess exposure, prioritize patching or mitigation, and verify system versions to prevent potential impact on network availability and reliability.

• Potential Denial of Service (DoS) on affected systems
• Need for patching or mitigation to prevent exploitation
• Possible impact on network availability and reliability
• Requirement for inventory checks and version verification

Technical summary

The vulnerability exists in the eventd service of Junos OS and Junos OS Evolved. A local attacker can exploit this by sending a crafted packet to the eventd relay service, leading to a Denial of Service (DoS). The vulnerability has a medium severity and can lead to Denial of Service (DoS) if exploited. System administrators and security teams should assess exposure, prioritize patching or mitigation, and verify system versions to prevent potential impact on network availability and reliability. This issue affects Junos OS and Junos OS Evolved versions prior to 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, and 26.2R1-S2.

Defensive priority

Medium priority for Junos OS and Junos OS Evolved systems, focusing on versions prior to 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, and 26.2R1-S2.

Recommended defensive actions

• Review and apply patches for affected Junos OS and Junos OS Evolved versions
• Restrict access to the eventd relay service
• Monitor for suspicious activity on Junos OS and Junos OS Evolved systems
• 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 in Junos OS and Junos OS Evolved. The NVD entry is currently not provided. The vulnerability has a medium severity and can lead to Denial of Service (DoS) if exploited. System administrators and security teams should assess exposure, prioritize patching or mitigation, and verify system versions to prevent potential impact on network availability and reliability.

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.