# CVE-2023-5347: Unauthenticated Firmware Upgrade

> Attackers can bypass signature verification to install malicious firmware on Korenix JetNet devices, gaining full control.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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:** 9 Jan 2024
- **Updated:** 8 Oct 2025
- **Also known as:** GHSA-3fr9-8m46-r2mm

## What is CVE-2023-5347?

CVE-2023-5347 is a critical vulnerability in Korenix JetNet Series, published on 9 Jan 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An Improper Verification of Cryptographic Signature vulnerability in the update process of Korenix JetNet Series allows replacing the whole operating system including Trusted Executables. This issue affects JetNet devices older than firmware version 2024/01.

Weakness: CWE-347 (Improper Verification of Cryptographic Signature), CWE-327 (Use of a Broken or Risky Cryptographic Algorithm)

## Which versions are affected by CVE-2023-5347?

It affects 42 products.


Products: Korenix Jetnet 4508-W Firmware, Korenix Jetnet 4508 Firmware, Korenix Jetnet 4508f-M Firmware, Korenix Jetnet 4508f-Mw Firmware, Korenix Jetnet 4508f-S Firmware, Korenix Jetnet 4508f-Sw Firmware, Korenix Jetnet 4508i-W Firmware, Korenix Jetnet 4508if-M Firmware, Korenix Jetnet 4508if-Mw Firmware, Korenix Jetnet 4508if-S Firmware, Korenix Jetnet 4508if-Sw Firmware, Korenix Jetnet 5310g Firmware, Korenix Jetnet 5612g-4f Firmware, Korenix Jetnet 5612gp-4f Firmware, Korenix Jetnet 5620g-4c Firmware, Korenix Jetnet 5728g-24p-Ac-2dc-Eu Firmware, Korenix Jetnet 5728g-24p-Ac-2dc-Us Firmware, Korenix Jetnet 6528gf-2ac-Eu Firmware, Korenix Jetnet 6528gf-2ac-Us Firmware, Korenix Jetnet 6528gf-2dc24 Firmware and 22 more.

## How do I fix CVE-2023-5347?

No fix has been published for CVE-2023-5347 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-5347 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-5347 exists.

## Other vulnerabilities in Korenix JetNet Series

- [CVE-2023-5376](https://insights.sbomify.com/CVE-2023-5376/): TFTP Without Authentication (high 8.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-5347 and fix it if it is affected.

What it is: CVE-2023-5347 is a critical vulnerability in Korenix JetNet Series, published on 9 Jan 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-5347 exists.

Affected product: Korenix JetNet Series. 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-2023-5347/ (Markdown: https://insights.sbomify.com/CVE-2023-5347/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-5347
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-5347
- OSV: https://osv.dev/vulnerability/CVE-2023-5347

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-5347/
Summaries are generated and may contain mistakes; the official description above is the record.