CVE-2021-0221
What it is
In an EVPN/VXLAN scenario, if an IRB interface with a virtual gateway address (VGA) is configured on a PE, a traffic loop may occur upon receipt of specific IP multicast traffic. The traffic loop will cause interface traffic to increase abnormally, ultimately leading to a Denial of Service (DoS) in packet processing. The following command could be used to monitor the interface traffic: user@junos> monitor interface traffic Interface Link Input packets (pps) Output packets (pps) et-0/0/1 Up 6492089274364 (70994959) 6492089235319 (70994956) et-0/0/25 Up 343458103 (1) 156844 (0) ae0 Up 9132519197257 (70994959) 9132519139454 (70994956) This issue affects Juniper Networks Junos OS on QFX Series: all versions prior to 17.3R3-S10; 17.4 versions prior to 17.4R2-S12, 17.4R3-S3; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S6; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R2-S5, 18.4R3-S5; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S3; 19.2 versions prior to 19.2R1-S5, 19.2R3-S1; 19.3 versions prior to 19.3R2-S5, 19.3R3; 19.4 versions prior to 19.4R2-S2, 19.4R3; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R1-S2, 20.2R2.
At a glance
- Exploitability
- Can be exploited from the same network segment without logging in. High risk of service disruption.
- Exploit odds
- 0.5% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.5% in the next 30 days (EPSS).
- Severity: 6.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.5% · EPSS, next 30 days
- Weakness
- CWE-703
- Record status
- Modified
Affected
- 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
Attack profile CVSS 3.1 · 6.5
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2021-0221.md and follow it. Check whether this project is affected by CVE-2021-0221. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
