# CVE-2021-40364: Information disclosure in SIMATIC PCS 7 V8.2

> Attackers with log file access can expose sensitive information, aiding further attacks on Siemens SIMATIC PCS 7 and WinCC systems.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C`)
- **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:** 9 Nov 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-h2gh-jqx7-wcj7

## What is CVE-2021-40364?

CVE-2021-40364 is a medium-severity vulnerability in Siemens SIMATIC PCS 7 V8.2, published on 9 Nov 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability has been identified in SIMATIC PCS 7 V8.2 (All versions), SIMATIC PCS 7 V9.0 (All versions < V9.0 SP3 UC04), SIMATIC PCS 7 V9.1 (All versions < V9.1 SP1), SIMATIC WinCC V15 and earlier (All versions < V15 SP1 Update 7), SIMATIC WinCC V16 (All versions < V16 Update 5), SIMATIC WinCC V17 (All versions < V17 Update 2), SIMATIC WinCC V7.4 (All versions < V7.4 SP1 Update 19), SIMATIC WinCC V7.5 (All versions < V7.5 SP2 Update 5). The affected systems store sensitive information in log files. An attacker with access to the log files could publicly expose the information or reuse it to develop further attacks on the system.

Weakness: CWE-532 (Insertion of Sensitive Information into Log File)

## Which versions are affected by CVE-2021-40364?

It affects 2 products.


Products: Siemens Simatic Pcs 7, Siemens Simatic Wincc.

## How do I fix CVE-2021-40364?

No fix has been published for CVE-2021-40364 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-40364 being exploited?

There is no known exploitation of CVE-2021-40364 in the wild and no public exploit code.

## Other vulnerabilities in Siemens SIMATIC PCS 7 V8.2

- [CVE-2023-25910](https://insights.sbomify.com/CVE-2023-25910/): Code injection in SIMATIC PCS 7 (critical 10.0)
- [CVE-2021-40358](https://insights.sbomify.com/CVE-2021-40358/): Path traversal in SIMATIC PCS 7 V8.2 (critical 9.9)
- [CVE-2019-10922](https://insights.sbomify.com/CVE-2019-10922/): Auth bypass in SIMATIC PCS 7 V8.0 and earlier (critical 9.8)
- [CVE-2021-40360](https://insights.sbomify.com/CVE-2021-40360/): Information disclosure in SIMATIC PCS 7 V8.2 (high 8.8)
- [CVE-2019-10916](https://insights.sbomify.com/CVE-2019-10916/): SQL injection in SIMATIC PCS 7 V8.0 and earlier (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-40364 and fix it if it is affected.

What it is: CVE-2021-40364 is a medium-severity vulnerability in Siemens SIMATIC PCS 7 V8.2, published on 9 Nov 2021. 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-2021-40364 in the wild and no public exploit code.

Affected product: Siemens SIMATIC PCS 7 V8.2. 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-2021-40364/ (Markdown: https://insights.sbomify.com/CVE-2021-40364/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-40364
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-40364
- OSV: https://osv.dev/vulnerability/CVE-2021-40364

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-40364/
Summaries are generated and may contain mistakes; the official description above is the record.