# CVE-2023-46156: Use after free in SIMATIC Drive Controller CPU 1504D TF

> Attackers can cause denial of service on Siemens SIMATIC controllers by sending crafted packets to port 102, requiring a restart to recover.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Dec 2023
- **Updated:** 25 Feb 2026
- **Also known as:** GHSA-5fwp-f47r-rg74

## What is CVE-2023-46156?

CVE-2023-46156 is a high-severity use after free vulnerability in Siemens SIMATIC Drive Controller CPU 1504D TF, published on 12 Dec 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Affected devices improperly handle specially crafted packets sent to port 102/tcp.
This could allow an attacker to create a denial of service condition. A restart is needed to restore
normal operations.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2023-46156?

It affects 73 products.


Products: Siemens Simatic Drive Controller Cpu 1504d Tf Firmware, Siemens Simatic Drive Controller Cpu 1507d Tf Firmware, Siemens Simatic Et 200sp Open Control 1515sp Pc2 Firmware, Siemens Simatic S7-1500 Cpu 1510sp-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1510sp F-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1511-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1511c-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1511f-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1511t-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1511tf-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1512c-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1512sp-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1512sp F-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1513-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1513f-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1513r-1 Pn Firmware, Siemens Simatic S7-1500 Cpu 1514sp-2 Pn Firmware, Siemens Simatic S7-1500 Cpu 1514sp F-2 Pn Firmware, Siemens Simatic S7-1500 Cpu 1514spt-2 Pn Firmware, Siemens Simatic S7-1500 Cpu 1514spt F-2 Pn Firmware and 53 more.

## How do I fix CVE-2023-46156?

No fix has been published for CVE-2023-46156 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-46156 being exploited?

There is no known exploitation of CVE-2023-46156 in the wild and no public exploit code.

## Other vulnerabilities in Siemens SIMATIC Drive Controller CPU 1504D TF

- [CVE-2022-38465](https://insights.sbomify.com/CVE-2022-38465/): Weak cryptography in SIMATIC Drive Controller family (critical 9.3)
- [CVE-2021-37185](https://insights.sbomify.com/CVE-2021-37185/): Denial of service in SIMATIC Drive Controller family (high 7.5)
- [CVE-2021-37204](https://insights.sbomify.com/CVE-2021-37204/): Denial of service in SIMATIC Drive Controller family (high 7.5)
- [CVE-2021-37205](https://insights.sbomify.com/CVE-2021-37205/): Denial of service in SIMATIC Drive Controller family (high 7.5)
- [CVE-2022-38773](https://insights.sbomify.com/CVE-2022-38773/): Security feature bypass in SIMATIC Drive Controller CPU 1504D TF (medium 4.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-46156 and fix it if it is affected.

What it is: CVE-2023-46156 is a high-severity use after free vulnerability in Siemens SIMATIC Drive Controller CPU 1504D TF, published on 12 Dec 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-2023-46156 in the wild and no public exploit code.

Affected product: Siemens SIMATIC Drive Controller CPU 1504D TF. 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-2023-46156/ (Markdown: https://insights.sbomify.com/CVE-2023-46156/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-46156
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-46156
- OSV: https://osv.dev/vulnerability/CVE-2023-46156

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-46156/
Summaries are generated and may contain mistakes; the official description above is the record.