External risk intelligence

Chrome for Android Shared Tab Groups Use After Free Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.6)

CVE-2026-84353

The vulnerability exists within the client-side browser application (Google Chrome on Android) and requires the user to be lured to a crafted HTML page to trigger the issue. As a client-side application typically used by end-users rather than acting as a public-facing network service or infrastructure component, it does not fit the criteria for a reachable internet-facing surface.

Use After Free

Halo Surface Signal: 1 out of 5 — much less likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A vulnerability in Google Chrome on Android related to Shared Tab Groups could allow a remote attacker to execute malicious code on a user's device through a compromised webpage. This is a critical issue that warrants attention to confirm its relevance to our environment.

  • A browser flaw could let attackers run code.
  • It affects user devices via web pages.
  • Confirm if this browser flaw impacts our users.

Attack Path

How an attacker could exploit the issue

An attacker could trick a user into visiting a malicious web page using social engineering. This page would exploit a use-after-free flaw in Chrome's Shared Tab Groups feature on Android. Successfully triggering this vulnerability allows the attacker to run their own code outside the browser's secure sandbox.

  • User visits a malicious page.
  • Crafted HTML page triggers flaw.
  • Attacker executes code outside sandbox.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability could allow a remote attacker, through social engineering, to execute arbitrary code on an affected Android device when a user visits a malicious HTML page. This could impact the device's integrity and confidentiality when the browser is used.

  • Arbitrary code execution on the device.
  • Via a crafted HTML page.
  • Compromised device integrity.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability affects Google Chrome on Android, placing responsibility primarily with end-users who interact with web content and potentially mobile device administrators or security teams responsible for managing application deployments. The first practical step is to confirm the presence of the affected Chrome version and assess the risk posed by potential user interaction with malicious web pages, followed by a coordinated remediation plan, likely involving user education and the eventual update of the browser.

  • End-users and mobile administrators own this issue.
  • Verify Chrome version and user exposure risk.
  • Plan user-directed updates or temporary mitigation.

Supplementary metadata

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

Frequently asked questions

What is Google Chrome for Android and how does it use Shared Tab Groups?

Google Chrome for Android is a widely used mobile web browser that allows users to access the internet, sync data, and manage sessions across devices. Shared Tab Groups is a specific feature within this browser that enables multiple users to collaborate by organizing and viewing the same sets of browser tabs collectively. This functionality requires complex memory management to track tab states and synchronization across different users.

What is a use-after-free vulnerability in the context of CVE-2026-84353?

A use-after-free, classified as CWE-416, occurs when a program continues to use a memory address after that memory has been cleared or released. In CVE-2026-84353, the browser incorrectly handles memory associated with Shared Tab Groups. If an attacker can manipulate this state, they may be able to force the browser to access invalid memory, potentially leading to unauthorized code execution outside of the browser's normal security boundaries.

How is this vulnerability triggered by an attacker?

An attacker must use social engineering to trick a user into visiting a specially crafted HTML page designed to exploit the memory management flaw. Simply having the browser installed is not enough to trigger the bug. The vulnerability does not activate through passive network traffic or background processes; it requires the user to actively navigate to and interact with the malicious web content.

Is my organization at high risk from this browser vulnerability?

According to Halo Surface Signal, this risk is considered very unlikely for your infrastructure. Because the flaw exists within a client-side application on mobile devices rather than a public-facing server or network service, it does not typically present a direct attack surface for your internal systems or external web services. The primary risk is to individual user devices rather than organizational network infrastructure.

How should I respond to CVE-2026-84353?

The most effective response is to ensure Chrome on Android is updated to version 152.0.7977.75 or later, which resolves the memory management issue. Administrators should verify the browser versions currently in use across mobile devices. Beyond updates, prioritize user awareness regarding the risks of navigating to untrusted or suspicious websites, as the exploit relies on enticing users to interact with malicious HTML content.

References