# CVE-2020-27771: Integer overflow in ImageMagick

> An integer overflow in ImageMagick's PDF processing allows attackers to cause a denial of service via crafted files.

- **Severity:** Low 3.3 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L`)
- **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:** 4 Dec 2020
- **Updated:** 4 Aug 2024
- **Also known as:** DEBIAN-CVE-2020-27771, GHSA-33vv-cq7w-wvpr, JLSEC-2026-869, UBUNTU-CVE-2020-27771

## What is CVE-2020-27771?

CVE-2020-27771 is a low-severity vulnerability in Debian Debian Linux, published on 4 Dec 2020. 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

In RestoreMSCWarning() of /coders/pdf.c there are several areas where calls to GetPixelIndex() could result in values outside the range of representable for the unsigned char type. The patch casts the return value of GetPixelIndex() to ssize_t type to avoid this bug. This undefined behavior could be triggered when ImageMagick processes a crafted pdf file. Red Hat Product Security marked this as Low severity because although it could potentially lead to an impact to application availability, no specific impact was demonstrated in this case. This flaw affects ImageMagick versions prior to 7.0.9-0.

Weakness: CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2020-27771?

It affects 3 products.


Products: Debian Debian Linux, Imagemagick Imagemagick, Redhat Enterprise Linux.

## How do I fix CVE-2020-27771?

Upgrade to a fixed version.

## Is CVE-2020-27771 being exploited?

There is no known exploitation of CVE-2020-27771 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-2020-27771 and fix it if it is affected.

What it is: CVE-2020-27771 is a low-severity vulnerability in Debian Debian Linux, published on 4 Dec 2020. 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-2020-27771 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-2020-27771/ (Markdown: https://insights.sbomify.com/CVE-2020-27771/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-27771
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-27771
- OSV: https://osv.dev/vulnerability/CVE-2020-27771

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-27771/
Summaries are generated and may contain mistakes; the official description above is the record.