# CVE-2021-35053: Denial of service in Kaspersky Endpoint Security for Windows

> An attacker can modify Firefox parameters to render the system unbootable, causing a denial of service on systems running Kaspersky Endpoint Security.

- **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:** 3 Nov 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-cc54-3ghq-hp7j

## What is CVE-2021-35053?

CVE-2021-35053 is a high-severity denial of service vulnerability in Kaspersky Endpoint Security for Windows, published on 3 Nov 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Possible system denial of service in case of arbitrary changing Firefox browser parameters. An attacker could change specific Firefox browser parameters file in a certain way and then reboot the system to make the system unbootable.

## Which versions are affected by CVE-2021-35053?

It affects 1 product.


Products: Kaspersky Endpoint Security.

## How do I fix CVE-2021-35053?

No fix has been published for CVE-2021-35053 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-35053 being exploited?

There is no known exploitation of CVE-2021-35053 in the wild and no public exploit code.

## Other vulnerabilities in Kaspersky Endpoint Security for Windows

- [CVE-2020-26200](https://insights.sbomify.com/CVE-2020-26200/): Security feature bypass in Kaspersky Endpoint Security with the Full Disk Encryption component installed (medium 6.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-35053 and fix it if it is affected.

What it is: CVE-2021-35053 is a high-severity denial of service vulnerability in Kaspersky Endpoint Security for Windows, published on 3 Nov 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-2021-35053 in the wild and no public exploit code.

Affected product: Kaspersky Endpoint Security for Windows. 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-2021-35053/ (Markdown: https://insights.sbomify.com/CVE-2021-35053/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-35053
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-35053
- OSV: https://osv.dev/vulnerability/CVE-2021-35053

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-35053/
Summaries are generated and may contain mistakes; the official description above is the record.