CVE-2025-9864 is a high-severity use-after-free vulnerability found in the V8 JavaScript engine component of Google Chrome versions prior to 140.0.7339.80. The vulnerability arises when the browser improperly manages memory, leading to a use-after-free condition. This flaw can be triggered remotely by an attacker who crafts a malicious HTML page containing specially designed JavaScript code. When a user visits such a page, the vulnerability can be exploited to cause heap corruption, potentially allowing the attacker to execute arbitrary code within the context of the browser process. The vulnerability does not require any privileges (PR:N) but does require user interaction (UI:R), meaning the victim must visit the malicious page. The CVSS v3.1 score of 8.8 reflects a high impact on confidentiality, integrity, and availability, with network attack vector and low attack complexity. Exploitation could lead to full compromise of the browser, enabling data theft, session hijacking, or further system compromise. Although no known exploits are currently reported in the wild, the nature of the vulnerability and its presence in a widely used browser make it a significant security concern. The vulnerability was published on September 3, 2025, and affects Chrome versions before 140.0.7339.80, for which a patch has presumably been released.

For European organizations, this vulnerability poses a substantial risk due to the widespread use of Google Chrome as a primary web browser across enterprises and public institutions. Successful exploitation could lead to unauthorized access to sensitive corporate data, including intellectual property, personal data protected under GDPR, and confidential communications. The ability to execute arbitrary code in the browser context could also facilitate lateral movement within networks, enabling attackers to escalate privileges or deploy additional malware. This is particularly critical for sectors such as finance, healthcare, and government agencies, where data confidentiality and integrity are paramount. Additionally, the vulnerability could be leveraged in targeted phishing campaigns or watering hole attacks, increasing the likelihood of successful exploitation. The requirement for user interaction means that social engineering remains a key factor, but given the scale of Chrome usage, the attack surface is extensive. The absence of known exploits in the wild currently provides a window for mitigation, but the high severity score indicates that organizations should act promptly to reduce risk.

European organizations should prioritize updating all instances of Google Chrome to version 140.0.7339.80 or later without delay. Automated patch management systems should be leveraged to ensure rapid deployment across all endpoints. In addition, organizations should implement browser security best practices such as disabling or restricting JavaScript execution from untrusted sources using Content Security Policy (CSP) headers. Employing endpoint protection solutions with behavior-based detection can help identify exploitation attempts. User awareness training should emphasize the risks of interacting with unsolicited links or suspicious websites to reduce the likelihood of user-initiated exploitation. Network-level protections, such as web filtering and intrusion prevention systems (IPS), can be configured to block access to known malicious domains or detect exploit payloads. Finally, organizations should monitor browser crash logs and unusual process behaviors that may indicate attempted exploitation.