# CVE-2021-38384: Incorrect Authorization in serverless-offline

> Serverless Offline returns 403 for trailing slashes unlike AWS, potentially leading developers to implement incorrect access controls and bypass security.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/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:** 10 Aug 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-h97f-5258-5593

## What is CVE-2021-38384?

CVE-2021-38384 is a critical missing authorization vulnerability in n/a, published on 10 Aug 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Serverless Offline 8.0.0 returns a 403 HTTP status code for a route that has a trailing / character, which might cause a developer to implement incorrect access control, because the actual behavior within the Amazon AWS environment is a 200 HTTP status code (i.e., possibly greater than expected permissions).

Weakness: CWE-755 (Improper Handling of Exceptional Conditions)

## Which versions are affected by CVE-2021-38384?

2 open source packages ship an affected version, including serverless-offline. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `serverless-offline` | npm | All versions to 8.0.0 | None |
| `serverless-offline` | npm | All versions to 8.0.0 | None |

Products: Serverless Offline Project Serverless Offline.

## How do I fix CVE-2021-38384?

No fix has been published for CVE-2021-38384 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-38384 being exploited?

There is no known exploitation of CVE-2021-38384 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-38384 and fix it if it is affected.

What it is: CVE-2021-38384 is a critical missing authorization vulnerability in n/a, published on 10 Aug 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-2021-38384 in the wild and no public exploit code.

Affected packages and fixed versions:
- serverless-offline (npm): affected all versions up to 8.0.0; no fix listed
- serverless-offline (npm): affected all versions up to 8.0.0; no fix listed

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-2021-38384/ (Markdown: https://insights.sbomify.com/CVE-2021-38384/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-38384
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-38384
- OSV: https://osv.dev/vulnerability/CVE-2021-38384

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-38384/
Summaries are generated and may contain mistakes; the official description above is the record.