Google has rolled out a new security feature in Chrome 146 that aims to stop attackers from hijacking user sessions through stolen cookies.
Quick Summary (TLDR):
- Google introduces Device Bound Session Credentials in Chrome 146 for Windows.
- Stops attackers from using stolen session cookies, even after 2FA is completed.
- Uses hardware level security like TPM and Secure Enclave to bind sessions to devices.
- Feature will expand to macOS in a future release.
What Happened?
Google has officially launched Device Bound Session Credentials in Chrome 146 for Windows users. The feature is designed to block session cookie theft, a growing method used by hackers to bypass login security, including two factor authentication.
The rollout follows earlier testing and industry collaboration, with Google reporting a noticeable drop in session theft incidents during trial phases.
How Session Cookie Theft Became a Major Threat?
Session cookies are small pieces of data that keep users logged into websites after authentication. These cookies often remain valid for long periods, making them a valuable target for attackers.
Cybercriminals are increasingly using infostealer malware to extract these cookies directly from a user’s device. Once stolen, these cookies allow attackers to access accounts without needing passwords or even 2FA codes.
- Reports suggest billions of session cookies have been stolen, with at least 17 billion compromised in 2024 alone.
- Around 94 billion stolen cookies are circulating on the dark web, highlighting the scale of the threat.
- Attackers often bundle and sell stolen session data for further exploitation.
What makes this attack especially dangerous is that the cookie already confirms successful login and 2FA verification. This means attackers can bypass traditional security layers entirely.
How Google Chrome 146 Fixes the Problem?
Google’s new Device Bound Session Credentials changes how authentication works by binding each session directly to the user’s device.
Here is how it works:
- Chrome uses hardware backed security modules such as the Trusted Platform Module on Windows.
- On macOS, it relies on the Secure Enclave.
- These systems generate a unique public and private key pair that cannot be exported from the device.
- Websites require proof that Chrome holds the correct private key before accepting a session.
Because attackers cannot access this private key, any stolen session cookie becomes useless almost immediately.
As Google explained, the browser must prove possession of the private key to the server before new session cookies are issued. Without this verification, stolen cookies expire quickly and cannot be reused.
A Shift from Reactive to Proactive Security
Until now, most defenses against session theft relied on detecting suspicious activity after a breach occurred. This reactive approach often failed against advanced malware.
Google says this new system marks a major shift.
The company said:
Even if malware manages to steal cookies, it cannot use them without access to the device bound private key.
Privacy Focused by Design
Google has emphasized that the new protocol is built with privacy in mind.
- Each session uses a distinct cryptographic key, preventing tracking across sites.
- Only minimal data is shared with servers.
- No device identifiers are exposed, reducing fingerprinting risks.
This ensures improved security without compromising user privacy.
Industry Collaboration and Future Plans
The Device Bound Session Credentials protocol was developed as an open web standard with input from industry players, including Microsoft, and contributions through the World Wide Web Consortium.
Google also worked with platforms like Okta during testing to ensure compatibility across real world applications.
Looking ahead, Google plans to expand the feature further:
- Support for federated identity systems like Single Sign On.
- Enhanced enterprise level security capabilities.
- Broader support for devices without dedicated hardware security.
The feature is currently available on Windows and is expected to arrive on macOS in an upcoming Chrome release.
SQ Magazine’s Takeaway
I think this is one of the most important security upgrades Chrome has introduced in years. The reality is that passwords and even 2FA are no longer enough when session cookies can be stolen so easily. By tying sessions directly to hardware, Google is closing a major gap that attackers have been exploiting at scale. If widely adopted by websites, this could significantly reduce account takeovers across the internet.
