# CVE-2021-42855: Local privilege escalation due to misconfigured write permission on .debug_command.config file

> Local attackers can escalate privileges and execute arbitrary commands by modifying the misconfigured .debug_command.config file used by the agent.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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 Mar 2022
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-j285-2pfr-phwh

## What is CVE-2021-42855?

CVE-2021-42855 is a high-severity vulnerability in Aternity SteelCentral AppInternals Dynamic Sampling Agent, published on 9 Mar 2022. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

It was discovered that the SteelCentral AppInternals Dynamic Sampling Agent (DSA) uses the ".debug_command.config" file to store a json string that contains a list of IDs and pre-configured commands. The config file is subsequently used by the "/api/appInternals/1.0/agent/configuration" API to map the corresponding ID to a command to be executed.

Weakness: CWE-732 (Incorrect Permission Assignment for Critical Resource), CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2021-42855?

It affects 1 product.


Products: Riverbed Steelcentral Appinternals Dynamic Sampling Agent.

## How do I fix CVE-2021-42855?

No fix has been published for CVE-2021-42855 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-42855 being exploited?

There is no known exploitation of CVE-2021-42855 in the wild and no public exploit code.

## Other vulnerabilities in Aternity SteelCentral AppInternals Dynamic Sampling Agent

- [CVE-2021-42786](https://insights.sbomify.com/CVE-2021-42786/): Remote Code Execution at AgentControllerServlet (critical 9.8)
- [CVE-2021-42854](https://insights.sbomify.com/CVE-2021-42854/): Directory Traversal Read/Write/Delete at PluginServlet (critical 9.8)
- [CVE-2021-42787](https://insights.sbomify.com/CVE-2021-42787/): Directory Traversal Write/Delete/Partial Read at AgentConfigurationServlet (critical 9.4)
- [CVE-2021-42853](https://insights.sbomify.com/CVE-2021-42853/): Directory Traversal Delete/Read at AgentDiagnosticServlet (critical 9.1)
- [CVE-2021-42857](https://insights.sbomify.com/CVE-2021-42857/): Directory Traversal Partial Write at AgentDaServlet (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-42855 and fix it if it is affected.

What it is: CVE-2021-42855 is a high-severity vulnerability in Aternity SteelCentral AppInternals Dynamic Sampling Agent, published on 9 Mar 2022. 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-2021-42855 in the wild and no public exploit code.

Affected product: Aternity SteelCentral AppInternals Dynamic Sampling Agent. 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-2021-42855/ (Markdown: https://insights.sbomify.com/CVE-2021-42855/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-42855
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-42855
- OSV: https://osv.dev/vulnerability/CVE-2021-42855

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From sbomify Insights: https://insights.sbomify.com/CVE-2021-42855/
Summaries are generated and may contain mistakes; the official description above is the record.