CVE-2026-5864: Google Chrome WebAudio Buffer Overflow

CVE-2026-5864 Overview

A heap buffer overflow vulnerability exists in the WebAudio component of Google Chrome prior to version 147.0.7727.55. This memory corruption flaw allows a remote attacker to potentially obtain sensitive information from process memory by enticing a victim to visit a specially crafted HTML page. The vulnerability is classified as CWE-122 (Heap-based Buffer Overflow) and has been assigned a high severity rating by the Chromium security team.

Critical Impact

Remote attackers can exploit this heap buffer overflow to read sensitive data from Chrome's process memory, potentially exposing credentials, session tokens, or other confidential information processed by the browser.

Affected Products

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

Discovery Timeline

• April 8, 2026 - CVE-2026-5864 published to NVD
• April 8, 2026 - Last updated in NVD database

Technical Details for CVE-2026-5864

Vulnerability Analysis

This vulnerability resides within the WebAudio API implementation in Google Chrome. WebAudio is a high-level JavaScript API for processing and synthesizing audio in web applications. The heap buffer overflow occurs when the WebAudio component improperly handles memory allocation during audio processing operations.

When exploited, this vulnerability allows an attacker to read beyond the allocated heap buffer boundaries, potentially exposing sensitive information stored in adjacent memory regions. This type of information disclosure can reveal memory contents including user data, authentication tokens, or internal browser state information that could be leveraged for further attacks.

The attack requires user interaction—specifically, the victim must navigate to a malicious webpage containing specially crafted HTML and JavaScript code designed to trigger the vulnerable code path in the WebAudio implementation.

Root Cause

The root cause of CVE-2026-5864 is improper bounds checking in the WebAudio component's memory management routines. When processing audio data, the component fails to properly validate buffer sizes before performing read operations, resulting in an out-of-bounds heap read condition. This allows memory contents beyond the intended buffer to be accessed and potentially leaked to the attacker.

Attack Vector

The attack vector for this vulnerability involves the following exploitation path:

1. An attacker creates a malicious webpage containing specially crafted HTML and JavaScript code
2. The malicious code utilizes the WebAudio API to trigger the vulnerable code path
3. When a victim visits the page, the WebAudio component processes the malicious audio data
4. The heap buffer overflow is triggered, allowing the attacker's JavaScript to read memory contents beyond the allocated buffer
5. Sensitive information from Chrome's process memory may be extracted and exfiltrated to the attacker

The vulnerability can be exploited remotely through a standard web browser session. Technical details regarding the specific exploitation mechanism can be found in the Chromium Issue Tracker Entry.

Detection Methods for CVE-2026-5864

Indicators of Compromise

• Unusual WebAudio API usage patterns in browser logs or network traffic
• Memory access violations or crashes in Chrome's renderer process
• Suspicious JavaScript code making excessive WebAudio API calls with malformed parameters
• Network connections to unknown domains following visits to untrusted websites

Detection Strategies

• Monitor for Chrome crash reports related to the WebAudio component or heap memory violations
• Implement browser extension or endpoint detection rules to identify malicious WebAudio API usage patterns
• Deploy network monitoring to detect exfiltration attempts following potential exploitation
• Use SentinelOne's behavioral AI to detect anomalous browser process behavior indicative of memory disclosure attacks

Monitoring Recommendations

• Enable Chrome's built-in crash reporting to capture potential exploitation attempts
• Deploy endpoint detection and response (EDR) solutions to monitor for suspicious browser memory access patterns
• Review web proxy logs for connections to known malicious domains hosting exploit code
• Implement Content Security Policy (CSP) headers to restrict WebAudio API usage on sensitive internal applications

How to Mitigate CVE-2026-5864

Immediate Actions Required

• Update Google Chrome to version 147.0.7727.55 or later immediately across all systems
• Enable automatic updates for Chrome to ensure timely patching of future vulnerabilities
• Restrict access to untrusted websites through web filtering or proxy policies
• Deploy SentinelOne endpoint protection to detect and prevent exploitation attempts

Patch Information

Google has released a security update addressing this vulnerability in Chrome version 147.0.7727.55. The fix corrects the improper bounds checking in the WebAudio component to prevent heap buffer overflow conditions. Administrators should update Chrome installations across their environment as soon as possible.

For detailed patch information, refer to the Chrome Releases Update.

Workarounds

• Disable JavaScript on untrusted websites using browser settings or extensions until patching is complete
• Use browser isolation technologies to sandbox web browsing sessions
• Implement network-level filtering to block access to known malicious domains
• Consider using alternative browsers temporarily while awaiting Chrome updates in controlled environments

# Verify Chrome version on Linux/macOS
google-chrome --version

# Force Chrome update check on Windows (PowerShell)
Start-Process "chrome://settings/help" -Wait

# Enterprise deployment: Update Chrome via package manager (Debian/Ubuntu)
sudo apt-get update && sudo apt-get install google-chrome-stable