CVE-2026-17903 in Chrome
Summary
by MITRE • 07/30/2026
Insufficient policy enforcement in Chromecast in Google Chrome prior to 151.0.7922.72 allowed an attacker on the local network segment to inject scripts or HTML into a privileged page via malicious network traffic. (Chromium security severity: Low)
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Analysis
by VulDB Data Team • 07/30/2026
This vulnerability represents a significant security weakness in the Chromecast integration within Google Chrome browsers, specifically affecting versions prior to 151.0.7922.72. The issue stems from inadequate policy enforcement mechanisms that fail to properly validate and sanitize network traffic originating from local network segments. When an attacker successfully injects malicious scripts or HTML content into a privileged page, they can potentially exploit this weakness to execute unauthorized code within the browser context, compromising the security of the affected system.
The technical flaw manifests as a failure in input validation and output sanitization within Chromecast's network communication handling. This vulnerability is classified under CWE-20 as "Improper Input Validation" and aligns with ATT&CK technique T1068 which describes "Exploitation for Privilege Escalation." The attack vector specifically targets the local network segment where the Chromecast device operates, allowing an attacker to manipulate network traffic without requiring direct physical access or complex exploitation techniques. The low severity classification from Chromium indicates that while the vulnerability does not directly compromise user data or system integrity, it provides a potential foothold for more sophisticated attacks.
The operational impact of this vulnerability extends beyond simple script injection, as it could enable attackers to perform man-in-the-middle attacks on Chromecast communications, potentially allowing them to manipulate media streaming content, intercept sensitive information transmitted through the device, or redirect users to malicious websites. This weakness particularly affects environments where local network security is not properly enforced, such as public networks or corporate environments with insufficient network segmentation.
Mitigation strategies should focus on immediate browser updates to version 151.0.7922.72 or later, which contain the necessary policy enforcement improvements. Network administrators should implement proper firewall rules to restrict unauthorized access to Chromecast devices and consider deploying network monitoring solutions that can detect anomalous traffic patterns associated with script injection attempts. Additionally, organizations should enforce strict network segmentation policies and regularly audit their local network configurations to prevent unauthorized devices from accessing sensitive network resources. The vulnerability demonstrates the critical importance of maintaining up-to-date security patches and implementing defense-in-depth strategies that protect against both external and internal network threats.