CVE-2022-3047 is a vulnerability in Google Chrome's Extensions API that affects versions prior to 105.0.5195.52. The root cause is insufficient policy enforcement related to the downloads policy when extensions are installed. Specifically, an attacker who convinces a user to install a malicious Chrome extension can exploit this vulnerability by using a crafted HTML page to bypass the intended downloads policy restrictions. This means that the malicious extension could initiate downloads that would otherwise be blocked or restricted by the browser's policy settings. The vulnerability is classified under CWE-602, which relates to insufficient control of a resource through its lifetime, indicating that the policy enforcement mechanisms do not adequately restrict extension behavior after installation. The CVSS v3.1 base score is 6.5 (medium severity), with the vector indicating that the attack requires no privileges (AV:N), low attack complexity (AC:L), no privileges required (PR:N), user interaction is required (UI:R), scope is unchanged (S:U), no confidentiality impact (C:N), high integrity impact (I:H), and no availability impact (A:N). There are no known exploits in the wild reported at the time of publication. The vulnerability was publicly disclosed on September 26, 2022, and Google has addressed it in Chrome version 105.0.5195.52 and later. The key technical risk is that malicious extensions can bypass download restrictions, potentially leading to unauthorized file downloads that could compromise system integrity or lead to further exploitation.

For European organizations, this vulnerability poses a significant risk primarily to the integrity of systems and data. Since the attack vector involves convincing users to install malicious extensions, organizations with users who frequently install browser extensions or have less stringent controls on browser configurations are at higher risk. The ability to bypass download policies can lead to unauthorized software or malware being downloaded and executed, potentially leading to further compromise such as data tampering, introduction of ransomware, or lateral movement within networks. This is particularly concerning for sectors with high regulatory requirements for data integrity and security, such as finance, healthcare, and critical infrastructure. Additionally, organizations relying heavily on Chrome as their primary browser must consider the risk of policy bypass leading to non-compliance with internal security policies or external regulations like GDPR if data integrity is compromised. Although no confidentiality impact is directly indicated, the integrity impact can indirectly affect confidentiality if malicious payloads are introduced. The requirement for user interaction (installing the extension) means that user awareness and training are critical factors in risk mitigation.

European organizations should implement a multi-layered mitigation strategy beyond simply updating Chrome to version 105.0.5195.52 or later. First, enforce strict policies on extension installation through enterprise-managed browser policies, allowing only vetted and approved extensions to be installed. Utilize Chrome Enterprise features to whitelist extensions and block all others. Second, implement endpoint protection solutions that monitor and block unauthorized downloads and execution of suspicious files, adding a layer of defense if a malicious extension is installed. Third, conduct regular user awareness training focused on the risks of installing untrusted browser extensions and recognizing social engineering attempts. Fourth, monitor network traffic for unusual download activity originating from browsers, which may indicate exploitation attempts. Fifth, maintain an up-to-date inventory of browser versions across the organization and deploy patches promptly. Finally, consider deploying application control or sandboxing technologies to limit the impact of any unauthorized downloads initiated by extensions.