A Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') vulnerability in the packet forwarding engine (PFE) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS). As part of the stateful traffic processing on SRX Series devices flows are being established, and removed when not needed anymore. During the removal process the timeout of a flow should be set to 3 seconds and consequentially the flow should be removed shortly after. Due to a race condition occurring when setting the timeout there is a chance (the exact conditions are outside the attackers control) that the timeout is instead set to a very high value of larger than 10,000 seconds: user@host> show security flow session | match timeout Session ID: 98784248524, Policy name: PROD-FLOW/4, HA State: Active, Timeout: 85250, Session State: Valid This will lead to an accumulation of flows which can be observed by an ever-increasing value of invalidated sessions in the output of 'show security flow session summary': user@host> show security flow session summary | match invalid Invalidated sessions: 216931These sessions can't be cleared manually with the 'clear security flow session' command, which will either lead to forwarding to stop (and the system needs to be manually recovered with a reboot) or to a flowd core and automatic reboot. This issue affects Junos OS on SRX Series: * 24.2 versions before 24.2R2-S3, * 24.4 versions before 24.4R2-S1, 24.4R2-S2, * 25.2 versions before 25.2R1-S2, 25.2R2. This issue does not affect releases earlier than 24.2R1;
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 5.9, indicating it can be exploited remotely over the network but requires specific conditions to be met without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts and availability (service disruption) for affected systems. Impacting 20 products from juniper, from juniper, from juniper and 17 others, organizations running these solutions should prioritize assessment and patching.
Reported in 2026, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2026-07-09T22:17:08.643
2026-07-13T20:16:07.750
Analyzed
CVSSv3.1: 5.9 (MEDIUM)
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Operating System | juniper | junos | 24.2 | Yes |
| Operating System | juniper | junos | 24.2 | Yes |
| Operating System | juniper | junos | 24.2 | Yes |
| Operating System | juniper | junos | 24.2 | Yes |
| Operating System | juniper | junos | 24.2 | Yes |
| Operating System | juniper | junos | 24.2 | Yes |
| Operating System | juniper | junos | 24.2 | Yes |
| Operating System | juniper | junos | 24.4 | Yes |
| Operating System | juniper | junos | 24.4 | Yes |
| Operating System | juniper | junos | 24.4 | Yes |
| Operating System | juniper | junos | 24.4 | Yes |
| Operating System | juniper | junos | 24.4 | Yes |
| Operating System | juniper | junos | 25.2 | Yes |
| Operating System | juniper | junos | 25.2 | Yes |
| Operating System | juniper | junos | 25.2 | Yes |
| Hardware | juniper | srx1500 | - | No |
| Hardware | juniper | srx1600 | - | No |
| Hardware | juniper | srx2300 | - | No |
| Hardware | juniper | srx300 | - | No |
| Hardware | juniper | srx320 | - | No |
| Hardware | juniper | srx340 | - | No |
| Hardware | juniper | srx345 | - | No |
| Hardware | juniper | srx380 | - | No |
| Hardware | juniper | srx400 | - | No |
| Hardware | juniper | srx4100 | - | No |
| Hardware | juniper | srx4120 | - | No |
| Hardware | juniper | srx4200 | - | No |
| Hardware | juniper | srx4300 | - | No |
| Hardware | juniper | srx440 | - | No |
| Hardware | juniper | srx4600 | - | No |
| Hardware | juniper | srx4700 | - | No |
| Hardware | juniper | srx5400 | - | No |
| Hardware | juniper | srx5600 | - | No |
| Hardware | juniper | srx5800 | - | No |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For juniper's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.