# CVE-2024-21604: Junos OS Evolved: A high rate of specific traffic will cause a complete system outage

> An unauthenticated attacker can cause a complete system outage in Junos OS Evolved by sending high-rate specific traffic, requiring an upgrade to fix.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Jan 2024
- **Updated:** 3 Jun 2025
- **Also known as:** GHSA-h4g9-rx7v-v6rf

## What is CVE-2024-21604?

CVE-2024-21604 is a high-severity denial of service vulnerability in Juniper Junos Os Evolved, published on 12 Jan 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An Allocation of Resources Without Limits or Throttling vulnerability in the kernel of Juniper Networks Junos OS Evolved allows an unauthenticated, network-based attacker to cause a Denial of Service (DoS).

If a high rate of specific valid packets are processed by the routing engine (RE) this will lead to a loss of connectivity of the RE with other components of the chassis and thereby a complete and persistent system outage. Please note that a carefully designed lo0 firewall filter will block or limit these packets which should prevent this issue from occurring.

The following log messages can be seen when this issue occurs:

<host> kernel: nf_conntrack: nf_conntrack: table full, dropping packet
This issue affects Juniper Networks Junos OS Evolved:

  *  All versions earlier than 20.4R3-S7-EVO;
  *  21.2R1-EVO and later versions;
  *  21.4-EVO versions earlier than 21.4R3-S5-EVO;
  *  22.1-EVO versions earlier than 22.1R3-S2-EVO;
  *  22.2-EVO versions earlier than 22.2R3-EVO;
  *  22.3-EVO versions earlier than 22.3R2-EVO;
  *  22.4-EVO versions earlier than 22.4R2-EVO.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2024-21604?

It affects 1 product.


Products: Juniper Junos Os Evolved.

## How do I fix CVE-2024-21604?

No fix has been published for CVE-2024-21604 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-21604 being exploited?

There is no known exploitation of CVE-2024-21604 in the wild and no public exploit code.

## Other vulnerabilities in Juniper Junos Os Evolved

- [CVE-2026-21902](https://insights.sbomify.com/CVE-2026-21902/): Junos OS Evolved: PTX Series: A vulnerability allows a unauthenticated, network-based attacker to execute code as root (critical 9.3)
- [CVE-2023-28983](https://insights.sbomify.com/CVE-2023-28983/): Junos OS Evolved: Shell Injection vulnerability in the gNOI server (high 8.8)
- [CVE-2025-21599](https://insights.sbomify.com/CVE-2025-21599/): Denial of service in Junos OS Evolved (high 8.7)
- [CVE-2024-47502](https://insights.sbomify.com/CVE-2024-47502/): Junos OS Evolved: TCP session state is not always cleared on the Routing Engine leading to DoS (high 8.7)
- [CVE-2024-39531](https://insights.sbomify.com/CVE-2024-39531/): Junos OS Evolved: ACX 7000 Series: Protocol specific DDoS configuration affects other protocols (high 8.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-21604 and fix it if it is affected.

What it is: CVE-2024-21604 is a high-severity denial of service vulnerability in Juniper Junos Os Evolved, published on 12 Jan 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-21604 in the wild and no public exploit code.

Affected product: Juniper Junos Os Evolved. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2024-21604/ (Markdown: https://insights.sbomify.com/CVE-2024-21604/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-21604
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-21604
- OSV: https://osv.dev/vulnerability/CVE-2024-21604

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-21604/
Summaries are generated and may contain mistakes; the official description above is the record.