# CVE-2024-30402: Junos OS and Junos OS Evolved: The l2ald crashes on receiving telemetry messages from a specific subscription

> An unauthenticated adjacent attacker can cause a sustained Denial of Service by triggering crashes in the l2ald daemon via telemetry requests.

- **Severity:** High 8.2 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Apr 2024
- **Updated:** 2 Aug 2024
- **Also known as:** GHSA-8vc5-fgcg-4vh9

## What is CVE-2024-30402?

CVE-2024-30402 is a high-severity denial of service vulnerability in Juniper Junos, published on 12 Apr 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Layer 2 Address Learning Daemon (l2ald) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker to cause a Denial of Service (DoS).

When telemetry requests are sent to the device, and the Dynamic Rendering Daemon (drend) is suspended, the l2ald crashes and restarts due to factors outside the attackers control. Repeated occurrences of these events causes a sustained DoS condition.

This issue affects:
Junos OS:
  *  All versions earlier than 20.4R3-S10;
  *  21.2 versions earlier than 21.2R3-S7;
  *  21.4 versions earlier than 21.4R3-S5;
  *  22.1 versions earlier than 22.1R3-S4;
  *  22.2 versions earlier than 22.2R3-S3;
  *  22.3 versions earlier than 22.3R3-S1;
  *  22.4 versions earlier than 22.4R3;
  *  23.2 versions earlier than 23.2R1-S2, 23.2R2.

Junos OS Evolved:

  *  All versions earlier than 21.4R3-S5-EVO;
  *  22.1-EVO versions earlier than 22.1R3-S4-EVO;
  *  22.2-EVO versions earlier than 22.2R3-S3-EVO;
  *  22.3-EVO versions earlier than 22.3R3-S1-EVO;
  *  22.4-EVO versions earlier than 22.4R3-EVO;
  *  23.2-EVO versions earlier than 23.2R2-EVO.

Weakness: CWE-754 (Improper Check for Unusual or Exceptional Conditions)

## Which versions are affected by CVE-2024-30402?

It affects 2 products.


Products: Juniper Junos, Juniper Junos Os Evolved.

## How do I fix CVE-2024-30402?

No fix has been published for CVE-2024-30402 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-30402 being exploited?

There is no known exploitation of CVE-2024-30402 in the wild and no public exploit code.

## Other vulnerabilities in Juniper Junos

- [CVE-2023-36845](https://insights.sbomify.com/CVE-2023-36845/): Juniper Junos OS EX Series and SRX Series PHP External Variable Modification (critical 9.8, exploited in the wild)
- [CVE-2020-1631](https://insights.sbomify.com/CVE-2020-1631/): Juniper Junos OS Path Traversal (high 8.8, exploited in the wild)
- [CVE-2025-21590](https://insights.sbomify.com/CVE-2025-21590/): Juniper Junos OS Improper Isolation or Compartmentalization (medium 6.7, exploited in the wild)
- [CVE-2023-36851](https://insights.sbomify.com/CVE-2023-36851/): Juniper Junos OS SRX Series Missing Authentication for Critical Function (medium 5.3, exploited in the wild)
- [CVE-2023-36844](https://insights.sbomify.com/CVE-2023-36844/): Juniper Junos OS EX Series PHP External Variable Modification (medium 5.3, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-30402 and fix it if it is affected.

What it is: CVE-2024-30402 is a high-severity denial of service vulnerability in Juniper Junos, published on 12 Apr 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-2024-30402 in the wild and no public exploit code.

Affected product: Juniper Junos. 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-2024-30402/ (Markdown: https://insights.sbomify.com/CVE-2024-30402/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-30402
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-30402
- OSV: https://osv.dev/vulnerability/CVE-2024-30402

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-30402/
Summaries are generated and may contain mistakes; the official description above is the record.