CVE-2025-14766: Google Chrome V8 RCE Vulnerability

CVE-2025-14766 Overview

CVE-2025-14766 is a high-severity out-of-bounds read and write vulnerability in the V8 JavaScript engine used by Google Chrome. The flaw affects all Chrome versions prior to 143.0.7499.147 across Windows, macOS, and Linux. A remote attacker can trigger heap corruption by convincing a user to load a crafted HTML page. Successful exploitation can lead to arbitrary code execution within the renderer process, providing a foothold for sandbox escape chains. Google addressed the issue in the December 16, 2025 stable channel update for desktop.

Critical Impact

Remote heap corruption in the V8 engine enables potential arbitrary code execution in the Chrome renderer process through a single malicious web page visit.

Affected Products

• Google Chrome prior to 143.0.7499.147 on Microsoft Windows
• Google Chrome prior to 143.0.7499.147 on Apple macOS
• Google Chrome prior to 143.0.7499.147 on Linux

Discovery Timeline

• 2025-12-16 - Google releases stable channel update for desktop addressing the flaw
• 2025-12-16 - CVE-2025-14766 published to NVD
• 2025-12-23 - Last updated in NVD database

Technical Details for CVE-2025-14766

Vulnerability Analysis

The vulnerability resides in V8, the open-source JavaScript and WebAssembly engine that powers Chrome and Chromium-based browsers. V8 compiles JavaScript to native machine code through its TurboFan and Maglev optimizing compilers. Memory safety errors in V8 routinely result in renderer-process compromise because the engine processes untrusted script from any visited website.

CVE-2025-14766 is classified under CWE-125 (Out-of-bounds Read) and additionally allows out-of-bounds writes. The combined read and write primitive on the V8 heap permits an attacker to corrupt adjacent JavaScript objects, hijack object pointers, and ultimately gain control of execution flow inside the renderer.

Root Cause

The root cause involves improper bounds validation in V8 when accessing heap-allocated objects. When the engine fails to verify the length or index of an indexed access, it reads beyond the allocated buffer and may write into adjacent memory. Such conditions typically arise from incorrect assumptions in speculative compiler optimizations or in built-in array operations. The Chromium issue tracker entry 466786677 tracks the underlying defect, with details restricted pending broad patch deployment.

Attack Vector

Exploitation requires a user to load attacker-controlled HTML containing crafted JavaScript. No authentication is required, and the entire payload is delivered over the network. Once the page executes, the JavaScript triggers the vulnerable V8 code path to produce the out-of-bounds primitive. Attackers chain heap-corruption primitives with type confusion or pointer overwrites to construct arbitrary read and write capabilities inside the renderer. Renderer code execution is commonly paired with a separate sandbox escape vulnerability to achieve full system compromise.

No verified exploitation code or proof of concept is publicly available at this time. See the Chromium Issue Tracker Entry for technical details once Google removes access restrictions.

Detection Methods for CVE-2025-14766

Indicators of Compromise

• Chrome renderer process crashes with heap corruption signatures originating from v8::internal frames
• Browser sessions visiting newly registered or low-reputation domains immediately preceding renderer instability
• Unexpected child processes spawned by chrome.exe following navigation to untrusted pages
• Outbound connections from Chrome to command-and-control infrastructure after script execution

Detection Strategies

• Inventory installed Chrome versions across managed endpoints and flag any build below 143.0.7499.147
• Monitor endpoint telemetry for Chrome renderer crashes coupled with subsequent process injection or shellcode execution
• Apply web proxy and DNS filtering to block access to known malicious or recently registered domains hosting exploit kits

Monitoring Recommendations

• Collect browser version telemetry through management tooling such as Chrome Browser Cloud Management or endpoint inventory agents
• Alert on parent-child process relationships where Chrome spawns shells, scripting engines, or LOLBins
• Forward browser, EDR, and proxy logs to a centralized analytics platform to correlate suspicious navigation with renderer anomalies

How to Mitigate CVE-2025-14766

Immediate Actions Required

• Update Google Chrome to version 143.0.7499.147 or later on all Windows, macOS, and Linux endpoints
• Restart Chrome on every managed device to ensure the patched binary is loaded into memory
• Update Chromium-based browsers, including Microsoft Edge, Brave, Opera, and Vivaldi, once their vendors ship the corresponding V8 fix

Patch Information

Google released the fix in the stable channel update for desktop on December 16, 2025. Administrators should consult the Google Chrome Desktop Update advisory for full version details and roll out the update through enterprise deployment tooling. Chrome's built-in updater applies the patch automatically after the next browser restart.

Workarounds

• Disable JavaScript for untrusted sites through Chrome enterprise policy DefaultJavaScriptSetting set to block, accepting the loss of functionality on many web applications
• Restrict browsing on sensitive systems to an allow-listed set of trusted internal domains until patching completes
• Enable Site Isolation and Strict Site Isolation policies to limit cross-origin impact from a compromised renderer

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

# Verify installed Chrome version on macOS
/Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --version

# Verify installed Chrome version on Windows (PowerShell)
(Get-Item "C:\Program Files\Google\Chrome\Application\chrome.exe").VersionInfo.ProductVersion