# CVE-2021-36121: File upload in n/a

> Authenticated attackers can upload arbitrary files to the Z: drive via directory traversal, achieving remote code execution as SYSTEM.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/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:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 Jul 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-wqqh-79fq-5fg5

## What is CVE-2021-36121?

CVE-2021-36121 is a high-severity vulnerability in n/a, published on 13 Jul 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

An issue was discovered in Echo ShareCare 8.15.5. The file-upload feature in Access/DownloadFeed_Mnt/FileUpload_Upd.cfm is susceptible to an unrestricted upload vulnerability via the name1 parameter, when processing remote input from an authenticated user, leading to the ability for arbitrary files to be written to arbitrary filesystem locations via ../ Directory Traversal on the Z: drive (a hard-coded drive letter where ShareCare application files reside) and remote code execution as the ShareCare service user (NT AUTHORITY\SYSTEM).

Weakness: CWE-434 (Unrestricted Upload of File with Dangerous Type)

## Which versions are affected by CVE-2021-36121?

It affects 1 product.


Products: Echobh Sharecare.

## How do I fix CVE-2021-36121?

No fix has been published for CVE-2021-36121 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-36121 being exploited?

There is no known exploitation of CVE-2021-36121 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2021-33578](https://insights.sbomify.com/CVE-2021-33578/): SQL injection in n/a (critical 9.8)
- [CVE-2021-36124](https://insights.sbomify.com/CVE-2021-36124/): Missing authorization in n/a (critical 9.8)
- [CVE-2021-36122](https://insights.sbomify.com/CVE-2021-36122/): Command injection in n/a (high 8.8)
- [CVE-2021-36123](https://insights.sbomify.com/CVE-2021-36123/): Path traversal in n/a (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-36121 and fix it if it is affected.

What it is: CVE-2021-36121 is a high-severity vulnerability in n/a, published on 13 Jul 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-36121 in the wild and no public exploit code.

Affected product: n/a. 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-2021-36121/ (Markdown: https://insights.sbomify.com/CVE-2021-36121/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-36121
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-36121
- OSV: https://osv.dev/vulnerability/CVE-2021-36121

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-36121/
Summaries are generated and may contain mistakes; the official description above is the record.