CVE-2025-4096 is a high-severity heap buffer overflow vulnerability identified in the HTML component of Google Chrome versions prior to 136.0.7103.59. This vulnerability arises from improper handling of heap memory during HTML processing, which can lead to heap corruption. An attacker can exploit this flaw by crafting a malicious HTML page that, when loaded by a vulnerable Chrome browser, triggers the heap buffer overflow. The overflow can corrupt adjacent memory structures, potentially allowing the attacker to execute arbitrary code, escalate privileges, or cause a denial of service (browser crash). The vulnerability is remotely exploitable without requiring any privileges or authentication, but it does require user interaction in the form of visiting or being redirected to a malicious webpage. The CVSS 3.1 base score is 8.8, reflecting high impact on confidentiality, integrity, and availability, as well as ease of exploitation over the network with low attack complexity. The vulnerability is categorized under CWE-122 (Heap-based Buffer Overflow), a common and dangerous class of memory corruption bugs. As of the published date, no known exploits have been reported in the wild, but the high severity and widespread use of Chrome make this a critical issue to address promptly.

For European organizations, this vulnerability poses a significant risk due to the widespread use of Google Chrome as a primary web browser across enterprises, government agencies, and critical infrastructure sectors. Exploitation could lead to unauthorized access to sensitive data, compromise of user credentials, and potential lateral movement within corporate networks if attackers gain code execution capabilities. The ability to execute arbitrary code remotely without authentication increases the threat landscape, especially for organizations with employees who frequently browse the internet or access external web content. Additionally, disruption caused by browser crashes or instability could impact productivity and operational continuity. Given the high confidentiality, integrity, and availability impacts, organizations handling sensitive personal data (e.g., GDPR-regulated data), financial information, or critical services are particularly vulnerable to data breaches and regulatory penalties if exploited.

European organizations should prioritize updating Google Chrome to version 136.0.7103.59 or later, where this vulnerability is patched. Since no patch links are currently provided, organizations should monitor official Google Chrome security advisories and deploy updates immediately upon release. In the interim, organizations can mitigate risk by implementing network-level protections such as web filtering to block access to untrusted or suspicious websites, and by enforcing strict content security policies to limit exposure to malicious HTML content. Employing endpoint detection and response (EDR) solutions to monitor for anomalous browser behavior and potential exploitation attempts is recommended. User awareness training should emphasize caution when clicking on unknown links or visiting untrusted sites. Additionally, organizations should consider isolating web browsing sessions using sandboxing or virtualization technologies to contain potential exploitation impacts. Regular vulnerability scanning and penetration testing can help identify residual risks related to browser vulnerabilities.