CVE-2025-6556 is a vulnerability identified in Google Chrome versions prior to 138.0.7204.49, specifically related to insufficient policy enforcement within the Loader component. The vulnerability allows a remote attacker to bypass the Content Security Policy (CSP) by crafting a malicious HTML page. CSP is a critical security mechanism designed to prevent cross-site scripting (XSS), data injection, and other code injection attacks by restricting the sources from which content can be loaded and executed. By bypassing CSP, an attacker could potentially execute unauthorized scripts or load malicious resources, undermining the browser's security model. The vulnerability is classified as low severity by the Chromium security team, indicating limited impact or exploitation complexity. There are no known exploits in the wild at the time of publication, and no CVSS score has been assigned. The vulnerability does not require user authentication but does require user interaction in the form of visiting or loading a crafted HTML page. The scope is limited to affected Chrome versions, which are widely used across multiple platforms. The lack of a patch link suggests that a fix may be pending or recently released but not yet documented in this source.

For European organizations, the impact of this vulnerability is primarily related to the potential circumvention of Content Security Policy protections, which could lead to client-side attacks such as cross-site scripting or data theft. While the Chromium team rates the severity as low, organizations relying heavily on Chrome for web access, especially those with sensitive web applications enforcing strict CSP rules, could face increased risk of targeted attacks. The vulnerability could be exploited to inject malicious scripts into trusted web pages, potentially leading to session hijacking, credential theft, or unauthorized data access. However, the requirement for user interaction (visiting a malicious page) limits the scope of automated exploitation. The absence of known exploits in the wild reduces immediate risk but does not eliminate the possibility of future attacks. European organizations with high web exposure, such as financial institutions, government agencies, and critical infrastructure operators, should consider this vulnerability in their threat models, especially given the widespread use of Chrome in Europe.

1. Immediate update to Google Chrome version 138.0.7204.49 or later once available to ensure the vulnerability is patched. 2. Implement network-level filtering to block access to known malicious or suspicious domains that could host crafted HTML pages exploiting this vulnerability. 3. Enhance endpoint security by deploying browser security extensions or policies that restrict script execution beyond CSP, such as enabling strict site isolation and sandboxing features. 4. Educate users on the risks of visiting untrusted websites and the importance of avoiding clicking on suspicious links or opening unknown attachments. 5. Monitor web traffic and browser behavior for anomalies that could indicate exploitation attempts, including unusual script execution or network requests. 6. For organizations deploying internal web applications, review and strengthen CSP configurations to minimize the impact of potential bypasses, including using nonce or hash-based CSP directives. 7. Employ web application firewalls (WAFs) that can detect and block malicious payloads targeting browser vulnerabilities.