# CVE-2019-0009: Junos OS: EX2300 and EX3400: High disk I/O operations may disrupt the communication between RE and PFE

> High disk I/O on Juniper EX2300/EX3400 switches disrupts RE-PFE communication, causing denial of service in virtual chassis deployments.

- **Severity:** Medium 5.5 (`CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Jan 2019
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-29c6-mr8r-mfmj

## What is CVE-2019-0009?

CVE-2019-0009 is a medium-severity denial of service vulnerability in Juniper Junos, published on 15 Jan 2019. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

On EX2300 and EX3400 series, high disk I/O operations may disrupt the communication between the routing engine (RE) and the packet forwarding engine (PFE). In a virtual chassis (VC) deployment, this issue disrupts communication between the VC members. This issue does not affect other Junos platforms. Affected releases are Junos OS on EX2300 and EX3400 series: 15.1X53 versions prior to 15.1X53-D590; 18.1 versions prior to 18.1R2-S2, 18.1R3; 18.2 versions prior to 18.2R2.

## Which versions are affected by CVE-2019-0009?

It affects 1 product.


Products: Juniper Junos.

## How do I fix CVE-2019-0009?

No fix has been published for CVE-2019-0009 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-0009 being exploited?

There is no known exploitation of CVE-2019-0009 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-2019-0009 and fix it if it is affected.

What it is: CVE-2019-0009 is a medium-severity denial of service vulnerability in Juniper Junos, published on 15 Jan 2019. 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-2019-0009 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-2019-0009/ (Markdown: https://insights.sbomify.com/CVE-2019-0009/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-0009
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-0009
- OSV: https://osv.dev/vulnerability/CVE-2019-0009

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-0009/
Summaries are generated and may contain mistakes; the official description above is the record.