CVE-2026-11307: Google Chrome Use-After-Free Vulnerability

CVE-2026-11307 Overview

CVE-2026-11307 is a use-after-free vulnerability in PDFium, the PDF rendering engine bundled with Google Chrome. The flaw affects versions of Chrome prior to 149.0.7827.53 across Windows, macOS, and Linux. A remote attacker can trigger memory corruption by enticing a user to open a crafted PDF file. Successful exploitation allows arbitrary code execution inside the Chrome renderer sandbox. The weakness is classified under CWE-416.

Critical Impact
Remote attackers can execute arbitrary code in the Chrome renderer process by delivering a crafted PDF, providing a foothold for sandbox escape chains.

Affected Products

Google Chrome versions prior to 149.0.7827.53
Chrome on Microsoft Windows, Apple macOS, and Linux
Embedded applications using PDFium for PDF rendering

Discovery Timeline

2026-06-05 - CVE-2026-11307 published to NVD
2026-06-08 - Last updated in NVD database

Technical Details for CVE-2026-11307

Vulnerability Analysis

The vulnerability is a use-after-free condition in PDFium, the open-source PDF parser and renderer that Chrome uses to display PDF documents. Use-after-free defects occur when code continues to reference heap memory after that memory has been released. The freed allocation can be reclaimed and overwritten by attacker-controlled data, causing the dangling pointer to operate on adversary-supplied content.

When Chrome processes a crafted PDF, the corrupted object can be reused during rendering, leading to controlled execution flow inside the renderer process. The renderer is sandboxed, so direct code execution is constrained to the renderer's privilege boundary. Attackers commonly chain this class of flaw with a separate sandbox escape to obtain full code execution on the host.

Root Cause

The root cause is improper lifetime management of a heap-allocated PDFium object. A reference to the object is retained and dereferenced after the object has been freed, satisfying the conditions described in CWE-416. Specific code paths and the affected object are not disclosed in the public advisory.

Attack Vector

Exploitation requires user interaction: the victim must load a malicious PDF in Chrome or visit a web page that embeds one. The attack vector is network-based and requires no authentication. Delivery channels include phishing emails containing PDF attachments, malicious advertising, and watering-hole pages that auto-load PDF resources. See the Google Chrome Stable Update and Chromium Issue Tracker Entry for additional context.

No verified proof-of-concept code is publicly available for CVE-2026-11307.
Refer to the Chromium issue tracker once Google releases full technical details.

Detection Methods for CVE-2026-11307

Indicators of Compromise

Chrome renderer process crashes (chrome.exe --type=renderer) correlated with PDF document loads
Unexpected child processes spawned by Chrome shortly after PDF rendering activity
Outbound network connections initiated by Chrome renderer processes to uncategorized or newly registered domains
PDF files with anomalous JavaScript objects, malformed cross-reference tables, or unusual embedded streams

Detection Strategies

Inventory installed Chrome versions across managed endpoints and flag any build below 149.0.7827.53
Inspect email and web gateways for PDF attachments containing obfuscated JavaScript or malformed object streams
Monitor endpoint telemetry for renderer crashes followed by post-exploitation behavior such as process injection or credential access

Monitoring Recommendations

Forward Chrome crash reports and EDR process telemetry to a centralized analytics platform for correlation
Track Chrome update compliance using management tooling and alert on stale versions
Hunt for PDF-borne payloads in proxy logs by reviewing downloads of PDFs from low-reputation sources

How to Mitigate CVE-2026-11307

Immediate Actions Required

Update Google Chrome to version 149.0.7827.53 or later on all Windows, macOS, and Linux endpoints
Force-restart Chrome after deployment to ensure the patched binary is loaded into memory
Audit and update third-party applications that bundle PDFium to vendor-patched releases

Patch Information

Google released the fix in the Chrome Stable channel at version 149.0.7827.53. Deployment details are available in the Google Chrome Stable Update announcement. Tracking information is available in the Chromium Issue Tracker Entry.

Workarounds

Disable the built-in PDF viewer via the PdfViewerEnabled enterprise policy and route PDFs to a hardened external reader
Block inbound PDF attachments at the email gateway from untrusted senders until patching is complete
Apply browser isolation or remote browser solutions for users handling untrusted PDF content

bash

# Verify Chrome version on Linux endpoints
google-chrome --version

# Example enterprise policy (Windows) to disable the built-in PDF viewer
reg add "HKLM\Software\Policies\Google\Chrome" /v PdfViewerEnabled /t REG_DWORD /d 0 /f