# CVE-2023-22391: Junos OS: ACX2K Series: Receipt of a high rate of specific traffic will lead to a Denial of Service (DoS)

> An unauthenticated attacker can cause a sustained Denial of Service on Juniper ACX2K devices by sending high-rate specific traffic that misclassifies into high-priority queues.

- **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 2023
- **Updated:** 7 Apr 2025
- **Also known as:** GHSA-hv3j-pf66-34pj

## What is CVE-2023-22391?

CVE-2023-22391 is a high-severity denial of service vulnerability in Juniper Junos, published on 12 Jan 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in class-of-service (CoS) queue management in Juniper Networks Junos OS on the ACX2K Series devices allows an unauthenticated network-based attacker to cause a Denial of Service (DoS). Specific packets are being incorrectly routed to a queue used for other high-priority traffic such as BGP, PIM, ICMP, ICMPV6 ND and ISAKMP. Due to this misclassification of traffic, receipt of a high rate of these specific packets will cause delays in the processing of other traffic, leading to a Denial of Service (DoS). Continued receipt of this amount of traffic will create a sustained Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS on ACX2K Series: All versions prior to 19.4R3-S9; All 20.2 versions; 20.3 versions prior to 20.3R3-S6 on ACX2K Series; 20.4 versions prior to 20.4R3-S4 on ACX2K Series; All 21.1 versions; 21.2 versions prior to 21.2R3-S3 on ACX2K Series. Note: This issues affects legacy ACX2K Series PPC-based devices. This platform reached Last Supported Version (LSV) as of the Junos OS 21.2 Release.

Weakness: CWE-755 (Improper Handling of Exceptional Conditions)

## Which versions are affected by CVE-2023-22391?

It affects 1 product.


Products: Juniper Junos.

## How do I fix CVE-2023-22391?

No fix has been published for CVE-2023-22391 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-22391 being exploited?

There is no known exploitation of CVE-2023-22391 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-2023-22391 and fix it if it is affected.

What it is: CVE-2023-22391 is a high-severity denial of service vulnerability in Juniper Junos, published on 12 Jan 2023. 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-2023-22391 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-2023-22391/ (Markdown: https://insights.sbomify.com/CVE-2023-22391/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-22391
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-22391
- OSV: https://osv.dev/vulnerability/CVE-2023-22391

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-22391/
Summaries are generated and may contain mistakes; the official description above is the record.
