# CVE-2024-30403: Junos OS Evolved: When MAC learning happens, and an interface gets flapped, the PFE crashes

> An unauthenticated adjacent attacker can cause a sustained Denial of Service by triggering a NULL pointer dereference in the Packet Forwarding Engine during interface flapping.

- **Severity:** High 7.1 (`CVSS:4.0/AV:A/AC:L/AT:N/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Apr 2024
- **Updated:** 2 Aug 2024
- **Also known as:** GHSA-hxmw-j74g-j23w

## What is CVE-2024-30403?

CVE-2024-30403 is a high-severity vulnerability in Juniper Junos Os Evolved, published on 12 Apr 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A NULL Pointer Dereference vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS Evolved allows an unauthenticated, adjacent attacker to cause a Denial of Service (DoS).

When Layer 2 traffic is sent through a logical interface, MAC learning happens. If during this process, the interface flaps, an Advanced Forwarding Toolkit manager (evo-aftmand-bt) core is observed. This leads to a PFE restart. The crash reoccurs if the same sequence of events happens, which will lead to a sustained DoS condition.

This issue affects Juniper Networks Junos OS Evolved 23.2-EVO versions earlier than 23.2R1-S1-EVO, 23.2R2-EVO.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2024-30403?

It affects 1 product.


Products: Juniper Junos Os Evolved.

## How do I fix CVE-2024-30403?

No fix has been published for CVE-2024-30403 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-30403 being exploited?

There is no known exploitation of CVE-2024-30403 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-2024-30403 and fix it if it is affected.

What it is: CVE-2024-30403 is a high-severity vulnerability in Juniper Junos Os Evolved, published on 12 Apr 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-30403 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-2024-30403/ (Markdown: https://insights.sbomify.com/CVE-2024-30403/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-30403
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-30403
- OSV: https://osv.dev/vulnerability/CVE-2024-30403

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-30403/
Summaries are generated and may contain mistakes; the official description above is the record.