CVE-2026-87510: Google Chrome FileAPI RCE Vulnerability

CVE-2026-87510 Overview

CVE-2026-87510 is an improper input validation vulnerability [CWE-20] in the FileAPI component of Google Chrome versions prior to 153.0.8010.36. A remote attacker who has already compromised the renderer process can leverage a crafted HTML page to execute arbitrary code outside the Chrome sandbox. Successful exploitation breaks the browser's core security boundary and grants code execution in a higher-privilege context.

Critical Impact

Attackers chaining this flaw with a renderer compromise can escape the Chrome sandbox and execute arbitrary code on the host, undermining the browser's primary isolation guarantee.

Affected Products

• Google Chrome desktop versions prior to 153.0.8010.36
• Chromium-based browsers incorporating the vulnerable FileAPI code path
• Downstream distributions that ship Chromium builds older than the fixed release

Discovery Timeline

• 2026-09-09 - CVE CVE-2026-87510 published to NVD
• 2026-09-10 - Last updated in NVD database

Technical Details for CVE-2026-87510

Vulnerability Analysis

The vulnerability resides in Chrome's FileAPI implementation, which provides web pages with structured access to file objects and blob data. Improper input validation on data crossing the renderer-to-browser process boundary allows a compromised renderer to influence privileged operations. The result is a sandbox escape, meaning code that should be constrained inside the renderer's low-privilege process can run outside those restrictions.

Exploitation requires two conditions. First, the attacker must have already achieved code execution in the renderer process, typically through a separate memory corruption or type confusion bug. Second, the victim must load or interact with a crafted HTML page. Because the sandbox is Chrome's last line of defense against fully weaponized web exploits, breaking it converts a contained renderer compromise into a full host compromise.

Root Cause

The root cause is missing or insufficient validation of untrusted input processed by the FileAPI interface. Chromium's multi-process model assumes the browser process treats all renderer-supplied data as hostile. When validation checks are incomplete, a malicious renderer can supply values that violate the invariants the browser process depends on, leading to unsafe operations executed with browser-process privileges.

Attack Vector

The attack requires network-based delivery of a crafted HTML page and user interaction to load that page. The attacker must also pre-position a renderer compromise, which raises exploitation complexity but is realistic in exploit chains that combine multiple Chrome bugs. No verified proof-of-concept code is published for this issue. Additional context is available in the Chromium Issue Tracker #532957878.

No public exploit is currently available, and this CVE is not listed in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2026-87510

Indicators of Compromise

• Chrome renderer or browser processes spawning unexpected child processes such as command shells or scripting hosts
• Unusual file system writes performed by the Chrome browser process outside standard profile directories
• Crashes or integrity failures logged by Chrome shortly after visits to untrusted web pages

Detection Strategies

• Inventory Chrome installations across the fleet and flag hosts running versions earlier than 153.0.8010.36
• Monitor endpoint telemetry for anomalous process lineage originating from chrome.exe or Chromium binaries
• Correlate browser crash reports with proxy and DNS logs to identify visits to attacker-controlled infrastructure preceding the crash

Monitoring Recommendations

• Enable and centralize Chrome enterprise reporting to capture version, extension, and crash telemetry
• Alert on child processes of Chrome that are not part of an approved baseline, such as cmd.exe, powershell.exe, or bash
• Track outbound connections from Chrome processes to newly registered or low-reputation domains

How to Mitigate CVE-2026-87510

Immediate Actions Required

• Update Google Chrome to version 153.0.8010.36 or later on all managed endpoints
• Force-restart Chrome after update deployment to ensure the patched binaries are loaded into memory
• Audit third-party Chromium-based browsers and apply vendor updates that incorporate the upstream fix

Patch Information

Google released a fix in the Chrome Stable channel at version 153.0.8010.36. Deployment details are documented in the Chrome Stable Update Announcement. Enterprises should push the update through their standard browser management channel and validate installed versions post-deployment.

Workarounds

• Restrict browsing to trusted sites through enterprise web filtering while patch deployment is in progress
• Enforce Chrome's site isolation and disable unnecessary extensions that increase renderer attack surface
• Apply least-privilege policies so users do not run browsers under administrative accounts

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

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

# Enterprise policy: enforce automatic updates (Windows registry)
reg add "HKLM\SOFTWARE\Policies\Google\Update" /v UpdateDefault /t REG_DWORD /d 1 /f