# CVE-2021-31891: Command injection in Desigo CC

> Unauthenticated remote attackers can execute arbitrary code with root privileges via command injection in Siemens building automation systems using the OIS extension.

- **Severity:** Critical 10.0 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/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:** 14 Sep 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-ch26-285q-m7w2

## What is CVE-2021-31891?

CVE-2021-31891 is a critical command injection vulnerability in Siemens Desigo CC, published on 14 Sep 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability has been identified in Desigo CC (All versions with OIS Extension Module), GMA-Manager (All versions with OIS running on Debian 9 or earlier), Operation Scheduler (All versions with OIS running on Debian 9 or earlier), Siveillance Control (All versions with OIS running on Debian 9 or earlier), Siveillance Control Pro (All versions). The affected application incorrectly neutralizes special elements in a specific HTTP GET request which could lead to command injection. An unauthenticated remote attacker could exploit this vulnerability to execute arbitrary code on the system with root privileges.

Weakness: CWE-78 (Improper Neutralization of Special Elements used in an OS Command)

## Which versions are affected by CVE-2021-31891?

It affects 5 products.


Products: Siemens Desigo Cc, Siemens Gma-Manager, Siemens Operation Scheduler, Siemens Siveillance Control, Siemens Siveillance Control Pro.

## How do I fix CVE-2021-31891?

No fix has been published for CVE-2021-31891 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-31891 being exploited?

There is no known exploitation of CVE-2021-31891 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-31891 and fix it if it is affected.

What it is: CVE-2021-31891 is a critical command injection vulnerability in Siemens Desigo CC, published on 14 Sep 2021. 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-2021-31891 in the wild and no public exploit code.

Affected product: Siemens Desigo CC. 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-2021-31891/ (Markdown: https://insights.sbomify.com/CVE-2021-31891/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-31891
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-31891
- OSV: https://osv.dev/vulnerability/CVE-2021-31891

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-31891/
Summaries are generated and may contain mistakes; the official description above is the record.