Chrome: Insufficient policy enforcement in Loader in Google Chrome (CVE-2025-4664) #shorts

Summary

Welcome to Security Brief, I’m your host. Today we’re diving into CVE-2025-4664, a high-severity Chrome vulnerability that’s already being exploited in the wild. The U.S. Cybersecurity and Infrastructure Security Agency confirmed active exploitation, and Google rushed out an update to patch this zero-day. We’ll break down what’s at stake and what you need to do to stay safe.

Product details

This issue affects Google Chrome versions prior to 136.0.7103.113 on desktop platforms. It was discovered in the Loader component of Chromium’s rendering engine. Google released a patched build 136.0.7103.113, and major Linux distributions such as Fedora have pushed updates that include this fix alongside other critical patches.

Vulnerability type summary

CVE-2025-4664 is classified as insufficient policy enforcement. In plain terms, Chrome’s same-origin protections failed under specific conditions, allowing a malicious page to bypass security policies and read data from another origin. Chromium’s security team rates this flaw as high severity due to the potential for sensitive data leakage.

Details of the vulnerability

Under certain circumstances, a crafted HTML page can manipulate the Loader’s policy checks to access cross-origin resources. An attacker hosting that page could trick a user into visiting it, then silently extract data from other sites the user is signed into. Because the exploit works without any user interaction beyond loading the page, detection can be difficult. CISA has confirmed real-world attacks, making prompt updates essential.

Conclusion

That wraps our deep dive into CVE-2025-4664. If you’re running Chrome, update to version 136.0.7103.113 or later immediately. Linux users should pull the latest distro patches, and everyone should remain vigilant for unexpected browser behavior. Thanks for listening to Security Brief—stay secure, and we’ll see you next time.

Watch the full video on YouTube: CVE-2025-4664

Remediation and exploitation details

This chain involves the following actors

  • Attacker: Remote adversary seeking to exfiltrate data across origins
  • End User: User running a vulnerable version of Google Chrome

This following systems are involved

  • Google Chrome (Render and execute web content): Contains a loader component with insufficient policy enforcement

Attack entry point

  • Crafted HTML page: A web page designed to invoke the flawed loader and bypass origin checks

Remediation actions

End User
Update Google Chrome to version 136.0.7103.113 or later
Google Chrome
System Administrator
Apply the Fedora 42 chromium update
Chromium on Fedora

Exploitation actions

Loader policy bypass

Attacker
Create a malicious HTML document
Google Chrome
Examples:
  • Define script or resource tags that point to protected endpoints on other domains
  • Embed directives that instruct the loader to fetch these cross-origin resources without proper checks

Social engineering or third-party hosting

Attacker
Distribute the malicious page to the target
Google Chrome
Examples:
  • Send the link via email or messaging service
  • Host the page on a compromised or attacker-controlled website

Invoke loader component with crafted resource references

Attacker
Trigger the loader flaw when the victim opens the page
Google Chrome
Examples:
  • Insert dynamic script elements that reference data from another origin
  • Use image or style tags that force a fetch from a protected domain

Stealth exfiltration

Attacker
Extract cross-origin data and send it back
Google Chrome
Examples:
  • Read the response payload from the other domain
  • Use an allowed channel to transmit the harvested data to the attacker server

Related Content

NOTE: The following related content has not been vetted and may be unsafe.

CVE database technical details

CVE ID
CVE-2025-4664
Description
Insufficient policy enforcement in Loader in Google Chrome prior to 136.0.7103.113 allowed a remote attacker to leak cross-origin data via a crafted HTML page. (Chromium security severity: High)
Provider
Chrome
CWE / problem types
Insufficient policy enforcement
Affected Software Versions
Google:Chrome:[{'version': '136.0.7103.113', 'status': 'affected', 'lessThan': '136.0.7103.113', 'versionType': 'custom'}]
Date Published
2025-05-14T17:41:06.667Z
Last Updated
2025-05-17T03:55:59.300Z