# CVE-2023-2673: PHOENIX CONTACT: FL/TC MGUARD prone to Improper Input Validation

> Improper input validation allows UDP packets to bypass firewall rules, enabling access to protected devices and flooding attacks.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 Jun 2023
- **Updated:** 3 Jan 2025
- **Also known as:** GHSA-fw3q-vjp3-89w5

## What is CVE-2023-2673?

CVE-2023-2673 is a medium-severity vulnerability in PHOENIX CONTACT FL MGUARD 2102, published on 13 Jun 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Improper Input Validation vulnerability in PHOENIX CONTACT FL/TC MGUARD Family in multiple versions may allow UDP packets to bypass the filter rules and access the solely connected device behind the MGUARD which can be used for flooding attacks.

Weakness: CWE-1287 (Improper Validation of Specified Type of Input)

## Which versions are affected by CVE-2023-2673?

It affects 26 products.


Products: Phoenixcontact Fl Mguard 2102 Firmware, Phoenixcontact Fl Mguard 4102 Pci Firmware, Phoenixcontact Fl Mguard 4102 Pcie Firmware, Phoenixcontact Fl Mguard 4302 Firmware, Phoenixcontact Fl Mguard Centerport Firmware, Phoenixcontact Fl Mguard Centerport Vpn-1000 Firmware, Phoenixcontact Fl Mguard Core Tx Firmware, Phoenixcontact Fl Mguard Core Tx Vpn Firmware, Phoenixcontact Fl Mguard Delta Tx\/Tx Firmware, Phoenixcontact Fl Mguard Delta Tx\/Tx Vpn Firmware, Phoenixcontact Fl Mguard Gt\/Gt Firmware, Phoenixcontact Fl Mguard Gt\/Gt Vpn Firmware, Phoenixcontact Fl Mguard Pci4000 Firmware, Phoenixcontact Fl Mguard Pci4000 Vpn Firmware, Phoenixcontact Fl Mguard Pcie4000 Firmware, Phoenixcontact Fl Mguard Pcie4000 Vpn Firmware, Phoenixcontact Fl Mguard Rs2000 Tx\/Tx-B Firmware, Phoenixcontact Fl Mguard Rs2000 Tx\/Tx Vpn Firmware, Phoenixcontact Fl Mguard Rs2005 Tx Vpn Firmware, Phoenixcontact Fl Mguard Rs4000 Tx\/Tx-M Firmware and 6 more.

## How do I fix CVE-2023-2673?

No fix has been published for CVE-2023-2673 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-2673 being exploited?

There is no known exploitation of CVE-2023-2673 in the wild and no public exploit code.

## Other vulnerabilities in PHOENIX CONTACT FL MGUARD 2102

- [CVE-2024-43385](https://insights.sbomify.com/CVE-2024-43385/): Phoenix Contact: OS command execution through PROXY_HTTP_PORT in mGuard devices (high 8.8)
- [CVE-2024-43386](https://insights.sbomify.com/CVE-2024-43386/): Phoenix Contact: OS command execution through EMAIL_NOTIFICATION.TO in mGuard devices. (high 8.8)
- [CVE-2024-43387](https://insights.sbomify.com/CVE-2024-43387/): Phoenix Contact: Access files due to improper neutralization of special elements in MGUARD devices (high 8.8)
- [CVE-2024-43388](https://insights.sbomify.com/CVE-2024-43388/): Phoenix Contact: SNMP reconfiguration due to improper input validation in MGUARD devices (high 8.8)
- [CVE-2024-7699](https://insights.sbomify.com/CVE-2024-7699/): Phoenix Contact: OS command execution in MGUARD products (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-2673 and fix it if it is affected.

What it is: CVE-2023-2673 is a medium-severity vulnerability in PHOENIX CONTACT FL MGUARD 2102, published on 13 Jun 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-2023-2673 in the wild and no public exploit code.

Affected product: PHOENIX CONTACT FL MGUARD 2102. 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-2023-2673/ (Markdown: https://insights.sbomify.com/CVE-2023-2673/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-2673
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-2673
- OSV: https://osv.dev/vulnerability/CVE-2023-2673

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-2673/
Summaries are generated and may contain mistakes; the official description above is the record.