CVE-2026-102081: Junos OS: SRX4000 Series, SRX5000 Series and MX Series with SPC3: With application services configured, high session churn causes memory leak which will ultimately impact traffic
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.
Use the CLI command show security monitoring to monitor the memory utilization of the PFEs on the FPCs.
This issue affects Junos OS on SRX Series and MX Series:
23.4 versions from 23.4R2-S3 before 23.4R2-S7; 24.2 versions from 24.2R2 before 24.2R2-S3; 24.4 versions before 24.4R2-S3; 25.2 versions before 25.2R1-S2, 25.2R2.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Juniper Junos OSto a version that resolves this vulnerability.Fixed in 23.4R2-S7 - Upgrade
Upgrade
Juniper Junos OSto a version that resolves this vulnerability.Fixed in 24.2R2-S3 - Upgrade
Upgrade
Juniper Junos OSto a version that resolves this vulnerability.Fixed in 24.4R2-S3 - Upgrade
Upgrade
Juniper Junos OSto a version that resolves this vulnerability.Fixed in 25.2R1-S2 - Upgrade
Upgrade
Juniper Junos OSto a version that resolves this vulnerability.Fixed in 25.2R2 - Upgrade
Upgrade
Juniper Junos OSto a version that resolves this vulnerability.Fixed in 25.4R1 - Compensating control
Use the CLI command `show security monitoring` to monitor PFE memory utilization on the FPCs.
Event History
Frequently Asked Questions
Which systems are exposed to this issue?
Affected systems are SRX4000 Series, SRX5000 Series with SPC3, and MX Series with SPC3 running an affected Junos OS release. At least one listed application service must be configured, such as ALGs, IDP/DPI, APPID, SECINTEL, AAMW, or AppQoE.
Does exploitation require authentication or user interaction?
No. An unauthenticated attacker can trigger the issue remotely by causing high connection-per-second churn.
How can I determine whether the issue is affecting a device?
Use the CLI command "show security monitoring" to monitor PFE memory utilization on the FPCs. Increasing or exhausted PFE memory may lead to impaired traffic processing.
Which releases contain fixes?
Fixed releases include 23.4R2-S7 or later in the 23.4R2 train, 24.2R2-S3 or later in the 24.2 train, 24.4R2-S3 or later in the 24.4 train, and 25.2R1-S2 or 25.2R2. Affected ranges include releases before those versions as specified.