CVE-2026-13893: Google Chrome Information Disclosure Flaw

CVE-2026-13893 Overview

CVE-2026-13893 affects Google Chrome versions prior to 150.0.7871.47. The vulnerability stems from insufficient validation of untrusted input in the WebUI component. A remote attacker can leak cross-origin data by delivering malicious network traffic to a user browsing with a vulnerable Chrome build. Chromium classifies the security severity as Medium, and the flaw maps to CWE-20: Improper Input Validation. Exploitation requires user interaction, typically visiting an attacker-controlled page or loading attacker-controlled content. Successful exploitation breaks the same-origin policy protections that isolate web content across origins.

Critical Impact
Remote attackers can leak cross-origin data from other web origins the victim has loaded, breaking browser isolation guarantees and exposing sensitive session or content data.

Affected Products

Google Chrome for Desktop versions prior to 150.0.7871.47
Chromium-based browsers inheriting the vulnerable WebUI code path
Systems running Chrome on Windows, macOS, and Linux prior to the fixed Stable channel release

Discovery Timeline

2026-06-30 - CVE-2026-13893 published to the National Vulnerability Database (NVD)
2026-07-02 - Last updated in NVD database

Technical Details for CVE-2026-13893

Vulnerability Analysis

The defect resides in Chrome's WebUI subsystem, which renders privileged browser interfaces such as chrome:// pages. WebUI code accepts input from renderer processes and network responses. When that input is not fully validated, an attacker can craft data that causes WebUI logic to expose content belonging to a different web origin.

Cross-origin data leaks in browser contexts commonly return session tokens, personal data, or authenticated response bodies from unrelated sites. The Chromium project categorizes the severity as Medium because exploitation requires user interaction and does not directly yield code execution.

The attack is network-reachable and requires no prior authentication. The confidentiality impact is High, while integrity and availability are unaffected, consistent with a data-disclosure primitive rather than a memory-corruption or execution flaw.

Root Cause

The root cause is improper input validation ([CWE-20]) inside a WebUI handler. The handler processes attacker-influenced values without enforcing origin or type constraints strong enough to prevent leakage across the same-origin boundary. Public technical detail remains restricted in the Chromium Issue Tracker #501729582 pending broad patch deployment.

Attack Vector

An attacker hosts or injects malicious content that a Chrome user loads. Chrome's WebUI processes the malformed input, and the response path exposes data from an origin other than the attacker's. The attacker then reads that data through the compromised WebUI channel. No credentials are required, and the attack succeeds over standard network traffic once the user visits the malicious content. See the Google Chrome Desktop Update advisory for release-level detail.

Detection Methods for CVE-2026-13893

Indicators of Compromise

Chrome browser processes making unexpected outbound requests to unfamiliar domains shortly after loading attacker-controlled pages
Browser telemetry showing unexpected access patterns to chrome:// WebUI endpoints from renderer processes
User reports of session anomalies, unexpected logouts, or account activity on sites visited during a browsing session

Detection Strategies

Inventory Chrome versions across managed endpoints and flag any build below 150.0.7871.47
Monitor endpoint browser telemetry for anomalous navigation chains that terminate on unknown hosts serving heavily obfuscated JavaScript
Correlate web proxy logs with endpoint browser process activity to identify suspicious cross-site request patterns

Monitoring Recommendations

Track Chrome auto-update status through enterprise management tools and alert on stalled updates
Enable browser policy reporting to a central SIEM to detect version drift and policy tampering
Review DNS and proxy telemetry for connections to newly registered domains that host active browser exploits

How to Mitigate CVE-2026-13893

Immediate Actions Required

Update Google Chrome to version 150.0.7871.47 or later on all desktop endpoints
Force restart of Chrome after update deployment to ensure the patched binary is loaded
Verify Chromium-based derivative browsers have absorbed the upstream fix before considering them remediated

Patch Information

Google released the fix in the Chrome Stable channel. Refer to the Google Chrome Desktop Update advisory for the corresponding Stable channel notes. Enterprise administrators should deploy the update through existing patch management workflows and confirm that endpoints report the fixed version.

Workarounds

Restrict user browsing to trusted sites through web proxy allow-listing until patches are applied
Disable or restrict access to non-essential chrome:// WebUI surfaces via enterprise policy where feasible
Educate users to avoid unknown links and untrusted network environments until Chrome is updated

bash

# Verify Chrome version on managed endpoints
google-chrome --version

# Windows: query installed Chrome version from the registry
reg query "HKLM\SOFTWARE\Google\Update\Clients\{8A69D345-D564-463C-AFF1-A69D9E530F96}" /v pv

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