---
id: "CVE-2026-121166"
kind: "vulnerability"
aliases: ["CVE-2026-121166"]
title: "Chrome: PDFium type confusion lets a crafted PDF run code"
severity: "high"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["chrome", "endpoints", "linux", "macos", "runtime", "windows"]
not_affected_if: ["chrome-updated", "pdf-viewing-disabled"]
published_at: "2026-11-03T21:17:24+00:00"
first_seen_at: "2026-11-03T21:19:23+00:00"
updated_at: "2026-11-03T21:23:23+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-121166", "first_seen_at": "2026-11-03T21:19:23+00:00"}]
---

# Chrome: PDFium type confusion lets a crafted PDF run code

A type confusion bug in PDFium, the PDF engine inside Google Chrome, lets a crafted PDF file execute arbitrary code inside the browser sandbox. Chromium rates it High severity, and the sources do not say whether it is exploited in the wild.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the Chrome version under Chrome menu > Help > About Google Chrome, or run `chrome --version` on a managed machine.
- Confirm the installed version is `157.0.8103.38` or later.

## Fix

- Google Chrome: move to `157.0.8103.38` or later.

## Timeline

- 2026-11-03T21:19:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-121166

## From the sources

Type confusion in PDFium in Google Chrome prior to 157.0.8103.38 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted PDF file. (Chromium security severity: High)

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_