Due to a vulnerability in DDoS protection in Juniper Networks Junos OS and Junos OS Evolved on QFX5K Series switches in a VXLAN configuration, instability might be experienced in the underlay network as a consequence of exceeding the default ddos-protection aggregate threshold. If an attacker on a client device on the overlay network sends a high volume of specific, legitimate traffic in the overlay network, due to an improperly detected DDoS violation, the leaf might not process certain L2 traffic, sent by spines in the underlay network. Continued receipt and processing of the high volume traffic will sustain the Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS on QFX5K Series: 17.3 versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R3-S5; 18.1 versions prior to 18.1R3-S13; 18.2 versions prior to 18.2R2-S8, 18.2R3-S8; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R1-S8, 18.4R2-S6, 18.4R3-S6; 19.1 versions prior to 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S2; 19.3 versions prior to 19.3R3-S2; 19.4 versions prior to 19.4R2-S4, 19.4R3-S1; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R2; 20.3 versions prior to 20.3R1-S2, 20.3R2. Juniper Networks Junos OS Evolved on QFX5220: All versions prior to 20.3R2-EVO.
This vulnerability carries a HIGH severity rating with a CVSS v3.1 score of 7.4, indicating it requires adjacent network access 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 9 products from juniper, from juniper, from juniper and 6 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.
2021-04-22T20:15:09.630
2026-06-17T03:29:38.190
Modified
CVSSv3.1: 7.4 (HIGH)
AV:A/AC:L/Au:N/C:N/I:N/A:P
6.5
2.9
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.3 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | Yes |
| Operating System | juniper | junos | 17.4 | 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 |
| 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 | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.2 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.3 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 18.4 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.1 | Yes |
| Operating System | juniper | junos | 19.2 | Yes |
| Operating System | juniper | junos | 19.2 | Yes |
| Operating System | juniper | junos | 19.2 | Yes |
| Operating System | juniper | junos | 19.2 | Yes |
| Operating System | juniper | junos | 19.2 | Yes |
| Operating System | juniper | junos | 19.2 | Yes |
| Operating System | juniper | junos | 19.2 | Yes |
| Operating System | juniper | junos | 19.2 | Yes |
| Operating System | juniper | junos | 19.2 | Yes |
| Operating System | juniper | junos | 19.2 | Yes |
| Operating System | juniper | junos | 19.2 | Yes |
| Operating System | juniper | junos | 19.3 | Yes |
| Operating System | juniper | junos | 19.3 | Yes |
| Operating System | juniper | junos | 19.3 | Yes |
| Operating System | juniper | junos | 19.3 | Yes |
| Operating System | juniper | junos | 19.3 | Yes |
| Operating System | juniper | junos | 19.3 | Yes |
| Operating System | juniper | junos | 19.3 | Yes |
| Operating System | juniper | junos | 19.3 | Yes |
| Operating System | juniper | junos | 19.3 | Yes |
| Operating System | juniper | junos | 19.3 | Yes |
| Operating System | juniper | junos | 19.3 | Yes |
| Operating System | juniper | junos | 19.4 | Yes |
| Operating System | juniper | junos | 19.4 | Yes |
| Operating System | juniper | junos | 19.4 | Yes |
| Operating System | juniper | junos | 19.4 | Yes |
| Operating System | juniper | junos | 19.4 | Yes |
| Operating System | juniper | junos | 19.4 | Yes |
| Operating System | juniper | junos | 19.4 | Yes |
| Operating System | juniper | junos | 19.4 | Yes |
| Operating System | juniper | junos | 19.4 | Yes |
| Operating System | juniper | junos | 20.1 | Yes |
| Operating System | juniper | junos | 20.1 | Yes |
| Operating System | juniper | junos | 20.1 | Yes |
| Operating System | juniper | junos | 20.1 | Yes |
| Operating System | juniper | junos | 20.1 | Yes |
| Operating System | juniper | junos | 20.2 | Yes |
| Operating System | juniper | junos | 20.2 | Yes |
| Operating System | juniper | junos | 20.2 | Yes |
| Operating System | juniper | junos | 20.2 | Yes |
| Operating System | juniper | junos | 20.3 | Yes |
| Operating System | juniper | junos | 20.3 | Yes |
| Hardware | juniper | qfx5100 | - | No |
| Hardware | juniper | qfx5110 | - | No |
| Hardware | juniper | qfx5120 | - | No |
| Hardware | juniper | qfx5130 | - | No |
| Hardware | juniper | qfx5200 | - | No |
| Hardware | juniper | qfx5210 | - | No |
| Hardware | juniper | qfx5220 | - | No |
| Operating System | juniper | junos_os_evolved | 18.3 | Yes |
| Operating System | juniper | junos_os_evolved | 19.1 | Yes |
| Operating System | juniper | junos_os_evolved | 19.1 | Yes |
| Operating System | juniper | junos_os_evolved | 19.2 | Yes |
| Operating System | juniper | junos_os_evolved | 19.2 | Yes |
| Operating System | juniper | junos_os_evolved | 19.3 | Yes |
| Operating System | juniper | junos_os_evolved | 19.3 | Yes |
| Operating System | juniper | junos_os_evolved | 20.1 | Yes |
| Operating System | juniper | junos_os_evolved | 20.1 | Yes |
| Operating System | juniper | junos_os_evolved | 20.2 | Yes |
| Operating System | juniper | junos_os_evolved | 20.2 | Yes |
| Operating System | juniper | junos_os_evolved | 20.3 | Yes |
| Hardware | juniper | qfx5220 | - | 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.