CVE-2026-102083: Junos OS: SRX Series: With WebFiltering enabled prolonged HTTP session load can cause a crash
An Improper Resource Locking vulnerability in the UTM processing of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).
When UTM WebFiltering is configured and the WebFiltering cloud server is unreachable, sustained HTTP traffic load may cause the UTM subsystem to crash and restart, which will lead to a complete service outage until the system has recovered. When category lookup requests cannot be completed, they accumulate internally. Under high load and specific timing conditions, an invalid internal state can occur during cleanup of pending WebFiltering lookups, resulting in a crash of the UTM process. This issue applies to both NextGeneration WebFiltering (NGWF) and Enhanced WebFiltering (EWF).
This issue affects Junos OS on SRX Series:
23.2 versions from 23.2R2 before 23.2R2-S7.7; 23.4 versions from 23.4R2 before 23.4R2-S8.13; 24.2 versions before 24.2R2-S5.5; 24.4 versions before 24.4R2-S4; 25.2 versions before 25.2R2-S1; 25.4 versions before 25.4R1-S3, 25.4R2.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Juniper Networks Junos OS on SRX Seriesto a version that resolves this vulnerability.Fixed in 23.2R2-S7.7 - Upgrade
Upgrade
Juniper Networks Junos OS on SRX Seriesto a version that resolves this vulnerability.Fixed in 23.4R2-S8.13 - Upgrade
Upgrade
Juniper Networks Junos OS on SRX Seriesto a version that resolves this vulnerability.Fixed in 24.2R2-S5.5 - Upgrade
Upgrade
Juniper Networks Junos OS on SRX Seriesto a version that resolves this vulnerability.Fixed in 24.4R2-S4 - Upgrade
Upgrade
Juniper Networks Junos OS on SRX Seriesto a version that resolves this vulnerability.Fixed in 25.2R2-S1 - Upgrade
Upgrade
Juniper Networks Junos OS on SRX Seriesto a version that resolves this vulnerability.Fixed in 25.4R1-S3 - Upgrade
Upgrade
Juniper Networks Junos OS on SRX Seriesto a version that resolves this vulnerability.Fixed in 25.4R2 - Upgrade
Upgrade
Juniper Networks Junos OS on SRX Seriesto a version that resolves this vulnerability.Fixed in 26.2R1
Event History
Frequently Asked Questions
Which deployments are exposed to this issue?
Affected deployments are SRX Series devices running one of the listed vulnerable Junos OS releases with UTM WebFiltering configured. Both NextGeneration WebFiltering (NGWF) and Enhanced WebFiltering (EWF) are affected, and the WebFiltering cloud server must be unreachable.
What does an attacker need to do to trigger the outage?
An unauthenticated network-based attacker must sustain HTTP traffic load while category lookup requests cannot be completed. Exploitation also depends on high load and specific timing conditions during cleanup of pending WebFiltering lookups.
What is the operational impact if exploitation succeeds?
The UTM subsystem can crash and restart, causing a complete service outage until the system recovers. The vulnerability affects availability only; no confidentiality or integrity impact is stated.
Which Junos OS releases contain fixes?
Fixed releases are 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S4, 25.2R2-S1, 25.4R1-S3, and 25.4R2. Earlier releases within the affected version ranges are vulnerable.