# CVE-2021-20671: File upload in GROWI

> Administrative users can exploit invalid file validation to overwrite server files, potentially leading to arbitrary code execution.

- **Severity:** High 7.2 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 10 Mar 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-84w3-v2m2-fj4m

## What is CVE-2021-20671?

CVE-2021-20671 is a high-severity vulnerability in WESEEK, Inc. GROWI, published on 10 Mar 2021. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

Invalid file validation on the upload feature in GROWI versions v4.2.2 allows a remote attacker with administrative privilege to overwrite the files on the server, which may lead to arbitrary code execution.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2021-20671?

It affects 1 product.


Products: Weseek Growi.

## How do I fix CVE-2021-20671?

No fix has been published for CVE-2021-20671 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-20671 being exploited?

There is no known exploitation of CVE-2021-20671 in the wild and no public exploit code.

## Other vulnerabilities in WESEEK, Inc. GROWI

- [CVE-2021-20736](https://insights.sbomify.com/CVE-2021-20736/): SQL injection in GROWI (critical 9.1)
- [CVE-2019-5968](https://insights.sbomify.com/CVE-2019-5968/): Cross-site request forgery in GROWI (high 8.8)
- [CVE-2021-20670](https://insights.sbomify.com/CVE-2021-20670/): Information disclosure in GROWI (high 7.5)
- [CVE-2020-5682](https://insights.sbomify.com/CVE-2020-5682/): Denial of service in GROWI (high 7.5)
- [CVE-2020-5683](https://insights.sbomify.com/CVE-2020-5683/): Path traversal in GROWI (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-20671 and fix it if it is affected.

What it is: CVE-2021-20671 is a high-severity vulnerability in WESEEK, Inc. GROWI, published on 10 Mar 2021. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-20671 in the wild and no public exploit code.

Affected product: WESEEK, Inc. GROWI. 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-2021-20671/ (Markdown: https://insights.sbomify.com/CVE-2021-20671/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-20671
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-20671
- OSV: https://osv.dev/vulnerability/CVE-2021-20671

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-20671/
Summaries are generated and may contain mistakes; the official description above is the record.