# CVE-2021-37253: Denial of service in n/a

> Attackers can cause denial of service in M-Files Web by sending crafted HTTP Range headers, though the vulnerability is disputed as a web server responsibility.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:** 5 Dec 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-gpcr-2fv6-73fj

## What is CVE-2021-37253?

CVE-2021-37253 is a high-severity denial of service vulnerability in n/a, published on 5 Dec 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

M-Files Web before 20.10.9524.1 allows a denial of service via overlapping ranges (in HTTP requests with crafted Range or Request-Range headers). NOTE: this is disputed because the range behavior is the responsibility of the web server, not the responsibility of the individual web application

Weakness: CWE-444 (Inconsistent Interpretation of HTTP Requests)

## Which versions are affected by CVE-2021-37253?

It affects 1 product.


Products: M-Files M-Files Web.

## How do I fix CVE-2021-37253?

No fix has been published for CVE-2021-37253 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-37253 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-37253 exists.

## Other vulnerabilities in n/a

- [CVE-2021-37254](https://insights.sbomify.com/CVE-2021-37254/): Information disclosure in n/a (high 7.5)
- [CVE-2025-3087](https://insights.sbomify.com/CVE-2025-3087/): Stored XSS Vulnerability in M-Files Web (medium 5.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-37253 and fix it if it is affected.

What it is: CVE-2021-37253 is a high-severity denial of service vulnerability in n/a, published on 5 Dec 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-37253 exists.

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-2021-37253/ (Markdown: https://insights.sbomify.com/CVE-2021-37253/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-37253
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-37253
- OSV: https://osv.dev/vulnerability/CVE-2021-37253

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-37253/
Summaries are generated and may contain mistakes; the official description above is the record.