CVE-2026-17947: Google Chrome Use-After-Free Vulnerability

CVE-2026-17947 Overview

CVE-2026-17947 is a use-after-free vulnerability [CWE-416] in the WebSockets component of Google Chrome versions prior to 151.0.7922.72. A remote attacker can exploit the flaw by luring a user to a crafted HTML page, potentially leading to a sandbox escape. Chromium's security team rated the underlying issue as Low severity, but a successful sandbox escape would allow attacker-controlled code to break out of the renderer's isolation boundary. The issue was addressed in the Chrome Stable Channel update referenced in Google's release notes.

Critical Impact
Successful exploitation could allow a remote attacker to escape the Chrome sandbox from a renderer context via a crafted HTML page delivered over the web.

Affected Products

Google Chrome Desktop versions prior to 151.0.7922.72
Chromium-based browsers sharing the affected WebSockets implementation
Embedded applications using vulnerable Chromium builds

Discovery Timeline

2026-07-30 - CVE-2026-17947 published to NVD
2026-07-30 - Last updated in NVD database

Technical Details for CVE-2026-17947

Vulnerability Analysis

The vulnerability is a use-after-free condition in Chrome's WebSockets implementation. Use-after-free defects occur when a program continues to access memory after it has been released back to the allocator. An attacker who controls the freed memory region can influence subsequent operations that dereference the stale pointer. In browser contexts, this class of defect is a common primitive for achieving arbitrary read/write within the renderer process. When combined with additional weaknesses, it can enable a sandbox escape, as noted in the Chromium advisory. The WebSockets code path is reachable from JavaScript running on any origin, making the attack surface broad and trivially accessible from a hostile HTML page.

Root Cause

The root cause is improper object lifetime management within the WebSockets component. Specific technical details have not been publicly disclosed while patch adoption progresses. See Chromium Issue #515438256 for tracking information as details are released.

Attack Vector

Exploitation requires a target user to load a crafted HTML page in a vulnerable Chrome build. The page issues WebSocket operations designed to trigger the use-after-free and manipulate freed memory. No authentication is required. The vulnerability manifests in the renderer process and, per the advisory, could be leveraged as part of a chain to escape the Chrome sandbox. Refer to the Google Chrome Desktop Update for the vendor's remediation notice.

Detection Methods for CVE-2026-17947

Indicators of Compromise

Chrome renderer process crashes with heap-corruption signatures originating from WebSocket-related call stacks
Unexpected child process creation from chrome.exe following user navigation to untrusted sites
Outbound WebSocket connections to newly registered or low-reputation domains preceding renderer instability

Detection Strategies

Inventory installed Chrome versions across the fleet and flag any build below 151.0.7922.72
Correlate browser crash telemetry with URL history to identify potential exploitation attempts
Monitor for post-exploitation behaviors such as unexpected process spawns, script interpreters, or LOLBins launched from Chrome

Monitoring Recommendations

Ingest browser and endpoint telemetry into a centralized data lake for cross-source correlation of exploit chains
Alert on anomalous WebSocket traffic patterns paired with browser crash events
Track browser version compliance continuously and prioritize hosts running unpatched Chromium-based clients

How to Mitigate CVE-2026-17947

Immediate Actions Required

Update Google Chrome to version 151.0.7922.72 or later on all Windows, macOS, and Linux endpoints
Restart Chrome after patch installation to ensure the vulnerable process image is unloaded
Audit third-party Chromium-based browsers and Electron applications for embedded vulnerable builds

Patch Information

Google addressed the vulnerability in the Chrome Stable Channel release documented in the Google Chrome Desktop Update. Administrators managing Chrome via enterprise policy should verify that automatic updates are enabled and that clients have successfully applied build 151.0.7922.72.

Workarounds

Restrict browsing to trusted sites via enterprise web filtering until patch deployment completes
Enforce Chrome's site isolation policy to reduce cross-origin renderer impact
Disable or block WebSocket connections at the network layer where operationally feasible

bash

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

# Windows: query installed version via registry
reg query "HKLM\SOFTWARE\Google\Chrome\BLBeacon" /v version