CVEvulnerability
CVE-2021-0259
7.4 HIGH
Official page ↗
- Status
- Modified
- Published
- 2021-04-22
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 7.4 HIGH — CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
- CVSS 2.0 ([email protected])
- 3.3 LOW — AV:A/AC:L/Au:N/C:N/I:N/A:P
- Weaknesses
- CWE-755
Description
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.
Affected configurations
• juniper junos 17.3
• juniper junos 17.4
• juniper junos 18.1
• juniper junos 18.2
• juniper junos 18.3
• juniper junos 18.4
• juniper junos 19.1
• juniper junos 19.2
• juniper junos 19.3
• juniper junos 19.4
• juniper junos 20.1
• juniper junos 20.2
• juniper junos 20.3
• juniper junos os evolved 18.3
• juniper junos os evolved 19.1
• juniper junos os evolved 19.2
• juniper junos os evolved 19.3
• juniper junos os evolved 20.1
• juniper junos os evolved 20.2
• juniper junos os evolved 20.3
Related
Weakness · CWE (1)
- CWE-755 Improper Handling of Exceptional Conditions weakness
References
- https://kb.juniper.net/JSA11150 Vendor Advisory
- https://kb.juniper.net/JSA11150 Vendor Advisory