# CVE-2021-33572: Denial-of-Service (DoS) Vulnerability

> Remote attackers can crash the F-Secure Linux Security anti-virus engine by sending large or fuzzed files, causing a denial of service.

- **Severity:** Low 3.5 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 21 Jun 2021
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-396f-8jhp-q236

## What is CVE-2021-33572?

CVE-2021-33572 is a low-severity denial of service vulnerability in F-Secure Products, published on 21 Jun 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

A Denial-of-Service (DoS) vulnerability was discovered in F-Secure Linux Security whereby the FSAVD component used in certain F-Secure products can crash while scanning larger packages/fuzzed files. The exploit can be triggered remotely by an attacker. A successful attack will result in Denial-of-Service (DoS) of the Anti-Virus engine.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2021-33572?

It affects 4 products.


Products: F-Secure Cloud Protection for Salesforce, F-Secure Elements for Microsoft 365, F-Secure Endpoint Protection, F-Secure Linux Security.

## How do I fix CVE-2021-33572?

No fix has been published for CVE-2021-33572 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-33572 being exploited?

There is no known exploitation of CVE-2021-33572 in the wild and no public exploit code.

## Other vulnerabilities in F-Secure Products

- [CVE-2020-9342](https://insights.sbomify.com/CVE-2020-9342/): Security feature bypass in n/a (medium 5.5)
- [CVE-2022-28886](https://insights.sbomify.com/CVE-2022-28886/): Denial-of-Service (DoS) Vulnerability (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-33572 and fix it if it is affected.

What it is: CVE-2021-33572 is a low-severity denial of service vulnerability in F-Secure Products, published on 21 Jun 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-33572 in the wild and no public exploit code.

Affected product: F-Secure Products. 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-2021-33572/ (Markdown: https://insights.sbomify.com/CVE-2021-33572/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-33572
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-33572
- OSV: https://osv.dev/vulnerability/CVE-2021-33572

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-33572/
Summaries are generated and may contain mistakes; the official description above is the record.