# CVE-2026-3308: CVE-2026-3308

> An integer overflow in MuPDF allows attackers to execute arbitrary code via a maliciously crafted PDF file.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/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:** 31 Mar 2026
- **Updated:** 21 Apr 2026
- **Also known as:** DEBIAN-CVE-2026-3308, GHSA-6jrq-hjxp-2x5r, UBUNTU-CVE-2026-3308

## What is CVE-2026-3308?

CVE-2026-3308 is a high-severity vulnerability in Artifex Software Inc. *PyMuPDF* MuPDF, published on 31 Mar 2026. 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 integer overflow vulnerability in 'pdf-image.c' in Artifex's MuPDF version 1.27.0 allows an attacker to maliciously craft a PDF that can trigger an integer overflow within the 'pdf_load_image_imp' function. This allows a heap out-of-bounds write that could be exploited for arbitrary code execution.

Weakness: CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2026-3308?


## How do I fix CVE-2026-3308?

Upgrade to a fixed version.

## Is CVE-2026-3308 being exploited?

There is no known exploitation of CVE-2026-3308 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-3308 and fix it if it is affected.

What it is: CVE-2026-3308 is a high-severity vulnerability in Artifex Software Inc. *PyMuPDF* MuPDF, published on 31 Mar 2026. 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-2026-3308 in the wild and no public exploit code.

Affected product: Artifex Software Inc. *PyMuPDF* MuPDF. 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-2026-3308/ (Markdown: https://insights.sbomify.com/CVE-2026-3308/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-3308
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-3308
- OSV: https://osv.dev/vulnerability/CVE-2026-3308

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-3308/
Summaries are generated and may contain mistakes; the official description above is the record.