CVE-2024-7233 is a local privilege escalation vulnerability identified in Avast Free Antivirus, specifically affecting the Avast Service component in version 24.2.6105 (build 24.2.8918.827). The root cause is an improper link resolution before file access, classified under CWE-59 (Improper Link Resolution Before File Access). The vulnerability allows a local attacker who already has the ability to execute low-privileged code on the target system to exploit the service by creating a symbolic link (symlink). The Avast Service follows this symlink improperly, which can be abused to delete arbitrary folders on the system. By leveraging this behavior, the attacker can escalate privileges from a low-privileged user to SYSTEM level, the highest privilege on Windows systems, enabling arbitrary code execution with full system control. The vulnerability does not require user interaction but does require local access and some level of code execution capability. The CVSS v3.0 score is 7.8, reflecting high impact on confidentiality, integrity, and availability, with low attack complexity and low privileges required. No public exploits or widespread exploitation have been reported as of the publication date. The vulnerability was reserved on July 29, 2024, and published on November 22, 2024. This flaw is significant because antivirus software runs with elevated privileges and is trusted by the operating system, so exploitation can lead to complete system compromise.

The impact of CVE-2024-7233 is substantial for organizations using the affected Avast Free Antivirus versions on Windows platforms. Successful exploitation allows attackers to escalate privileges from a low-privileged user to SYSTEM, enabling full control over the affected machine. This can lead to unauthorized access to sensitive data, installation of persistent malware, disabling of security controls, and lateral movement within networks. Since antivirus software is a critical security component, compromising it undermines the entire security posture of an organization. Attackers with local access, such as through phishing, compromised endpoints, or insider threats, can leverage this vulnerability to gain elevated privileges without detection. This increases the risk of data breaches, ransomware deployment, and disruption of business operations. The vulnerability affects confidentiality, integrity, and availability of systems, making it a high-risk issue for enterprises, government agencies, and critical infrastructure operators.

1. Apply official patches or updates from Avast as soon as they become available to address CVE-2024-7233. 2. Until patches are released, restrict local user permissions to prevent unauthorized code execution or symbolic link creation, especially on systems running Avast Free Antivirus. 3. Implement application whitelisting and endpoint detection and response (EDR) solutions to monitor and block suspicious symbolic link creation or manipulation activities. 4. Regularly audit and monitor file system changes and Avast service logs for unusual behavior indicative of exploitation attempts. 5. Employ the principle of least privilege for all users and services to minimize the attack surface. 6. Educate users about the risks of executing untrusted code locally, as initial low-privileged code execution is a prerequisite for exploitation. 7. Consider deploying alternative antivirus solutions with no known similar vulnerabilities if patching is delayed. 8. Maintain comprehensive backups and incident response plans to quickly recover from potential compromises.