CVE-2026-5909: Google Chrome Media Integer Overflow RCE

CVE-2026-5909 Overview

CVE-2026-5909 is an integer overflow vulnerability in the Media component of Google Chrome prior to version 147.0.7727.55. This vulnerability allows a remote attacker to potentially exploit heap corruption via a crafted video file. The flaw occurs when the browser processes specially crafted media content, leading to memory corruption that could be leveraged for arbitrary code execution.

Critical Impact

Remote attackers can exploit this heap corruption vulnerability by delivering malicious video files to users, potentially leading to complete system compromise without requiring any privileges on the target system.

Affected Products

• Google Chrome versions prior to 147.0.7727.55
• Chromium-based browsers using vulnerable Media component versions
• Desktop platforms running affected Chrome versions (Windows, macOS, Linux)

Discovery Timeline

• 2026-04-08 - CVE-2026-5909 published to NVD
• 2026-04-09 - Last updated in NVD database

Technical Details for CVE-2026-5909

Vulnerability Analysis

This vulnerability stems from an integer overflow condition in Google Chrome's Media processing component. When Chrome parses video files, certain arithmetic operations on media stream parameters can overflow, resulting in incorrect memory allocation sizes. This leads to heap corruption when the actual data exceeds the undersized buffer allocation.

The vulnerability is classified under CWE-472 (External Control of Assumed-Immutable Web Parameter), indicating that external input influences critical memory operations. The attack requires user interaction—specifically, the victim must open or stream a malicious video file—but requires no privileges on the target system.

Successful exploitation could allow an attacker to achieve arbitrary code execution within the context of the browser process, potentially leading to data theft, credential harvesting, or lateral movement within the victim's environment.

Root Cause

The root cause is an integer overflow in the Media component's handling of video file metadata or stream parameters. When calculating buffer sizes for media data, the code fails to properly validate that arithmetic operations on size values do not overflow. This results in the allocation of an insufficiently sized heap buffer, which is subsequently overwritten when the actual media data is copied into it.

Integer overflow vulnerabilities in multimedia processing are particularly dangerous because media files are routinely opened from untrusted sources, including websites, email attachments, and messaging applications.

Attack Vector

The attack vector is network-based, requiring user interaction to trigger the vulnerability. An attacker could exploit this flaw through several methods:

1. Malicious Website: Hosting a crafted video file on a web page that automatically plays when visited
2. Email Attachment: Sending a malicious video file as an attachment
3. Social Engineering: Tricking users into downloading and opening crafted video files
4. Compromised Media: Injecting malicious video content into legitimate streaming services or content delivery networks

The vulnerability in the Media component means that standard video playback actions trigger the exploit path, making it highly exploitable through everyday browsing activities.

Detection Methods for CVE-2026-5909

Indicators of Compromise

• Unexpected Chrome renderer process crashes when opening video files
• Abnormal memory consumption patterns in Chrome's Media component
• Chrome process spawning unexpected child processes after video playback
• Suspicious network connections originating from Chrome following media file access

Detection Strategies

• Monitor for Chrome browser crashes with heap corruption signatures in crash dumps
• Implement network monitoring to detect download of suspicious video files with anomalous metadata
• Deploy endpoint detection to identify exploitation attempts through behavioral analysis of Chrome processes
• Utilize sandbox escape detection mechanisms to identify post-exploitation activity

Monitoring Recommendations

• Enable Chrome's crash reporting to collect telemetry on Media component failures
• Implement web filtering to block access to known malicious domains hosting exploit content
• Monitor for unusual Chrome process behavior including unexpected memory allocations and child process spawning
• Review endpoint logs for Chrome stability issues correlated with video file access

How to Mitigate CVE-2026-5909

Immediate Actions Required

• Update Google Chrome to version 147.0.7727.55 or later immediately
• Enable automatic updates for Chrome to ensure timely patching of future vulnerabilities
• Review browser policies to restrict autoplay of media content from untrusted sources
• Consider implementing application whitelisting for allowed media sources in enterprise environments

Patch Information

Google has addressed this vulnerability in Chrome version 147.0.7727.55. The fix is available through Chrome's standard update mechanism. Organizations should prioritize deployment of this update across all managed endpoints.

For additional details, refer to the Google Chrome Update Announcement and the Chromium Issue Tracker Entry.

Workarounds

• Disable automatic video playback in Chrome settings until the patch can be applied
• Implement content security policies that restrict media sources to trusted domains
• Use browser isolation technologies to contain potential exploitation attempts
• Consider temporarily using alternative browsers in high-security environments until patching is complete

# Chrome policy configuration to restrict media autoplay (Windows Registry)
# Import via Group Policy or direct registry modification
reg add "HKLM\SOFTWARE\Policies\Google\Chrome" /v AutoplayAllowed /t REG_DWORD /d 0 /f
reg add "HKLM\SOFTWARE\Policies\Google\Chrome\AutoplayAllowlist" /v 1 /t REG_SZ /d "https://trusted-domain.com" /f