Overview

ChromeAlone is a red team Command and Control (C2) implant that leverages the Chromium browser as its operating base. Developed by Praetorian and introduced at DEF CON 33, it transforms a trusted browser into a full-featured C2 agent, enabling credential theft, session hijacking, file system access, and persistence via the Isolated Web App framework.

Unlike conventional implants such as Meterpreter or commercial frameworks like Cobalt Strike, ChromeAlone blends into regular user activity by “living off the browser.” Since Chromium is widely deployed and often implicitly trusted, this approach makes detection significantly more challenging.

Key Features

• Browser-native implant: Operates inside Chromium, reducing anomaly signals compared to standalone agents.
• Credential capture: Extracts login sessions and authentication data directly from the browser environment.
• Session hijacking: Leverages active user sessions for lateral movement or privilege escalation.
• File system access: Reads and exfiltrates files using the browser’s sandboxed capabilities.
• Persistence via Isolated Web App: Survives reboots by masquerading as a legitimate installed web app.
• Extensible modules: Supports development of custom payloads and new tasking options.

Installation

ChromeAlone is distributed as a GitHub project with Dockerised deployment scripts. Basic setup involves cloning the repository and building the implant and relay infrastructure.

The repository includes a sideloader script that can install the Chromium implant on a target system. Relay servers can be deployed on AWS or other cloud infrastructure to proxy traffic back to the operator.

Usage

Once installed, ChromeAlone implants a beacon back to the C2 operator through encrypted channels. The tasking system supports everyday operations:

Operators interact with the implant through a control console or relay interface, issuing commands and receiving results in near real-time.

Attack Scenario

A red team gains a foothold on a corporate workstation but wishes to avoid traditional implants that might trigger endpoint detection. They sideload ChromeAlone into the user’s Chromium browser.

From that moment, the implant appears as standard browser activity while enabling the operator to:

• Capture cached corporate SSO credentials
• Hijack authenticated cloud sessions to pivot without triggering login alerts
• Establish persistence through an Isolated Web App install, ensuring survival across reboots

By living inside the browser, ChromeAlone blends into a trusted process, evading behavioural detection and making attribution difficult.

Red Team Relevance

Browser-based implants are not new, but ChromeAlone packages the concept into an accessible and production-ready framework. For operators, it provides a stealthier alternative to frameworks like Havoc or Cobalt Strike. For defenders, it highlights the need to monitor browser extensions, Isolated Web App usage, and unusual file system access initiated by browser processes.

Related tooling previously covered on darknet.org.uk includes Havoc C2 and Meterpreter, which remain standard in red team operations but rely on separate agents. ChromeAlone shifts the paradigm into a trusted, everyday application.

Conclusion

ChromeAlone demonstrates how trusted applications like browsers can be weaponised into covert C2 implants. For red teams, it offers a stealthy alternative to traditional frameworks, embedding command and control into an environment that defenders are less likely to scrutinise. For blue teams, it highlights blind spots around browser-based persistence and the need to monitor emerging abuse of Isolated Web Apps.

ChromeAlone is more than a proof of concept, it’s a signal that future C2 frameworks will continue to shift into the very applications defenders trust the most.

You can read more or download ChromeAlone here: https://github.com/praetorian-inc/ChromeAlone