# CVE-2021-33634: Malicious image running containers may cause DoS attacks

> Malicious container images can cause denial of service in iSulad using the default lcr+lxc runtime, affecting openEuler systems.

- **Severity:** Medium 6.3 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 29 Oct 2023
- **Updated:** 9 Sep 2024
- **Also known as:** GHSA-5mrv-f9xf-hpqp, OESA-2023-1692

## What is CVE-2021-33634?

CVE-2021-33634 is a medium-severity denial of service vulnerability in openEuler lcr, published on 29 Oct 2023. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

iSulad uses the lcr+lxc runtime (default) to run malicious images, which can cause DOS.

Weakness: CWE-665 (Improper Initialization)

## Which versions are affected by CVE-2021-33634?

It affects 1 product.


Products: Openeuler Icr.

## How do I fix CVE-2021-33634?

Apply the vendor's patch.

## Is CVE-2021-33634 being exploited?

There is no known exploitation of CVE-2021-33634 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-33634 and fix it if it is affected.

What it is: CVE-2021-33634 is a medium-severity denial of service vulnerability in openEuler lcr, published on 29 Oct 2023. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-33634 in the wild and no public exploit code.

Affected product: openEuler lcr. 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-2021-33634/ (Markdown: https://insights.sbomify.com/CVE-2021-33634/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-33634
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-33634
- OSV: https://osv.dev/vulnerability/CVE-2021-33634

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-33634/
Summaries are generated and may contain mistakes; the official description above is the record.