# CVE-2021-40358: Path traversal in SIMATIC PCS 7 V8.2

> Attackers can exploit path traversal in the web server to read, write, or delete critical files outside the restricted directory.

- **Severity:** Critical 9.9 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:O/RC:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 9 Nov 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-rcjv-2hj5-3cmq

## What is CVE-2021-40358?

CVE-2021-40358 is a critical path traversal vulnerability in Siemens SIMATIC PCS 7 V8.2, published on 9 Nov 2021. Any signed-in user can exploit it over the 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). Legitimate file operations on the web server of the affected systems do not properly neutralize special elements within the pathname. An attacker could then cause the pathname to resolve to a location outside of the restricted directory on the server and read, write or delete unexpected critical files.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2021-40358?

It affects 2 products.


Products: Siemens Simatic Pcs 7, Siemens Simatic Wincc.

## How do I fix CVE-2021-40358?

No fix has been published for CVE-2021-40358 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-40358 being exploited?

There is no known exploitation of CVE-2021-40358 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-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)
- [CVE-2019-10918](https://insights.sbomify.com/CVE-2019-10918/): Privilege escalation in SIMATIC PCS 7 V8.0 and earlier (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-40358 and fix it if it is affected.

What it is: CVE-2021-40358 is a critical path traversal vulnerability in Siemens SIMATIC PCS 7 V8.2, published on 9 Nov 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-40358 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-2021-40358/ (Markdown: https://insights.sbomify.com/CVE-2021-40358/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-40358
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-40358
- OSV: https://osv.dev/vulnerability/CVE-2021-40358

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-40358/
Summaries are generated and may contain mistakes; the official description above is the record.