# CVE-2021-3561: Memory corruption in fig2dev

> A crafted input can trigger an out-of-bounds write in fig2dev, leading to application crashes or potential memory corruption.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/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:** 26 May 2021
- **Updated:** 3 Aug 2024
- **Also known as:** DEBIAN-CVE-2021-3561, GHSA-w359-m9m3-v2w3, MGASA-2021-0379, UBUNTU-CVE-2021-3561

## What is CVE-2021-3561?

CVE-2021-3561 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 26 May 2021. 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

An Out of Bounds flaw was found fig2dev version 3.2.8a. A flawed bounds check in read_objects() could allow an attacker to provide a crafted malicious input causing the application to either crash or in some cases cause memory corruption. The highest threat from this vulnerability is to integrity as well as system availability.

Weakness: CWE-787 (Out-of-bounds Write), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2021-3561?

It affects 3 products.


Products: Debian Debian Linux, Fedoraproject Fedora, Fig2dev Project Fig2dev.

## How do I fix CVE-2021-3561?

Apply the vendor's patch.

## Is CVE-2021-3561 being exploited?

There is no known exploitation of CVE-2021-3561 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-3561 and fix it if it is affected.

What it is: CVE-2021-3561 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 26 May 2021. 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-2021-3561 in the wild and no public exploit code.

Affected product: Debian Debian Linux. 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-2021-3561/ (Markdown: https://insights.sbomify.com/CVE-2021-3561/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-3561
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-3561
- OSV: https://osv.dev/vulnerability/CVE-2021-3561

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-3561/
Summaries are generated and may contain mistakes; the official description above is the record.
