# CVE-2023-20881: Missing authorization in Cloud Controller API

> Attackers can override other users' syslog drain credentials by exploiting missing authorization checks in Cloud Foundry CAPI.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H`)
- **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:** 19 May 2023
- **Updated:** 21 Jan 2025
- **Also known as:** GHSA-gwjh-7ghx-8gww

## What is CVE-2023-20881?

CVE-2023-20881 is a high-severity missing authorization vulnerability in Cloud Controller API, published on 19 May 2023. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Cloud foundry instances having CAPI version between 1.140 and 1.152.0 along with loggregator-agent v7+ may override other users syslog drain credentials if they're aware of the client certificate used for that syslog drain. This applies even if the drain has zero certs. This would allow the user to override the private key and add or modify a certificate authority used for the connection.

Weakness: CWE-295 (Improper Certificate Validation)

## Which versions are affected by CVE-2023-20881?

It affects 3 products.


Products: Cloudfoundry Capi-Release, Cloudfoundry Cf-Deployment, Cloudfoundry Loggregator-Agent.

## How do I fix CVE-2023-20881?

No fix has been published for CVE-2023-20881 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-20881 being exploited?

There is no known exploitation of CVE-2023-20881 in the wild and no public exploit code.

## Other vulnerabilities in Cloud Controller API

- [CVE-2018-1195](https://insights.sbomify.com/CVE-2018-1195/): Auth bypass in Cloud Controller (high 8.8)
- [CVE-2020-5417](https://insights.sbomify.com/CVE-2020-5417/): Cloud Controller may allow developers to claim sensitive routes (high 8.5)
- [CVE-2018-1266](https://insights.sbomify.com/CVE-2018-1266/): Path traversal in n/a (high 8.1)
- [CVE-2020-5400](https://insights.sbomify.com/CVE-2020-5400/): Cloud Controller logs environment variables from app manifests (high 8.0)
- [CVE-2017-8033](https://insights.sbomify.com/CVE-2017-8033/): Path traversal in Cloud Controller API CAPI-release versions prior to v1.35.0 and cf-release versions prior to v268 (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-20881 and fix it if it is affected.

What it is: CVE-2023-20881 is a high-severity missing authorization vulnerability in Cloud Controller API, published on 19 May 2023. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-20881 in the wild and no public exploit code.

Affected product: Cloud Controller API. 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-2023-20881/ (Markdown: https://insights.sbomify.com/CVE-2023-20881/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-20881
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-20881
- OSV: https://osv.dev/vulnerability/CVE-2023-20881

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-20881/
Summaries are generated and may contain mistakes; the official description above is the record.