CVE-2026-102081 Juniper Networks CVE debrief

Who should care

Defenders responsible for Juniper Networks Junos OS on SRX4000 Series, SRX5000 Series with SPC3, and MX Series with SPC3 should assess exposure and prioritize verification and remediation.

Why it matters

A memory leak vulnerability in Juniper Networks Junos OS on SRX Series and MX Series devices can cause a Denial-of-Service (DoS) when specific application services are configured and high session churn occurs. Defenders should prioritize verifying and upgrading to non-affected Junos OS versions and monitoring memory utilization.

• Verify Junos OS versions to prevent potential DoS
• Monitor PFE memory utilization to detect potential issues
• Upgrade to non-affected versions to prevent exploitation

Technical summary

A Missing Release of Memory after Effective Lifetime vulnerability in the packet forwarding engine (PFE) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a complete Denial-of-Service (DoS). On SRX4000 Series, and SRX5000 Series with SPC3, and MX Series with SPC3, when one or more specific application services like ALGs, IDP/DPI, APPID, SECINTEL, AAMW or AppQoE are configured, a high connections per second churn will cause PFE memory to leak. If the memory is exhausted traffic processing will be impacted.

Defensive priority

Defenders should prioritize verifying and upgrading to non-affected Junos OS versions on SRX4000 Series, SRX5000 Series with SPC3, and MX Series with SPC3, and monitor memory utilization of PFEs on FPCs.

Recommended defensive actions

• Verify Junos OS versions on SRX4000 Series, SRX5000 Series with SPC3, and MX Series with SPC3
• Upgrade to non-affected Junos OS versions
• Monitor memory utilization of PFEs on FPCs using show security monitoring
• 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, affected versions, and potential impact. However, no additional information on exploitation or victim data is available. The vulnerability affects Junos OS versions 23.4 from 23.4R2-S3 before 23.4R2-S7, 24.2 from 24.2R2 before 24.2R2-S3, 24.4 before 24.4R2-S3, and 25.2 before 25.2R1-S2, 25.2R2. Defenders should verify Junos OS versions and monitor memory utilization of PFEs on FPCs.

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.