On PTX Series and QFX10k Series devices with the "inline-jflow" feature enabled, a use after free weakness in the Packet Forwarding Engine (PFE) microkernel architecture of Juniper Networks Junos OS may allow an attacker to cause a Denial of Service (DoS) condition whereby one or more Flexible PIC Concentrators (FPCs) may restart. As this is a race condition situation this issue become more likely to be hit when network instability occurs, such as but not limited to BGP/IGP reconvergences, and/or further likely to occur when more active "traffic flows" are occurring through the device. When this issue occurs, it will cause one or more FPCs to restart unexpectedly. During FPC restarts core files will be generated. While the core file is generated traffic will be disrupted. Sustained receipt of large traffic flows and reconvergence-like situations may sustain the Denial of Service (DoS) situation. This issue affects: Juniper Networks Junos OS: 18.1 version 18.1R2 and later versions prior to 18.1R3-S10 on PTX Series, QFX10K Series.
This vulnerability carries a HIGH severity rating with a CVSS v3.1 score of 7.5, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts and availability (service disruption) for affected systems. Impacting 13 products from juniper, from juniper, from juniper and 10 others, organizations running these solutions should prioritize assessment and patching.
Reported in 2021, 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.
2021-04-22T20:15:10.017
2026-06-17T03:29:40.087
Modified
CVSSv3.1: 7.5 (HIGH)
AV:N/AC:M/Au:N/C:N/I:N/A:P
8.6
2.9
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Operating System | juniper | junos | 18.1 | Yes |
| Hardware | juniper | ptx1000 | - | No |
| Hardware | juniper | ptx10001-36mr | - | No |
| Hardware | juniper | ptx10002 | - | No |
| Hardware | juniper | ptx10003 | - | No |
| Hardware | juniper | ptx10004 | - | No |
| Hardware | juniper | ptx10008 | - | No |
| Hardware | juniper | ptx10016 | - | No |
| Hardware | juniper | ptx3000 | - | No |
| Hardware | juniper | ptx5000 | - | No |
| Hardware | juniper | qfx10002 | - | No |
| Hardware | juniper | qfx10008 | - | No |
| Hardware | juniper | qfx10016 | - | 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.