CVE-2025-13032 is a critical security vulnerability identified in Avast Antivirus products (Free, Premium, Ultimate editions) for Windows platforms prior to version 25.3. The root cause is a Time-of-check to Time-of-use (TOCTOU) race condition classified under CWE-367, specifically a double fetch issue within the sandbox kernel driver component. This race condition allows a local attacker to exploit a timing window between the verification of data and its subsequent use, leading to a pool overflow in kernel memory. The overflow can be leveraged to execute arbitrary code with elevated privileges, effectively escalating the attacker's rights from a limited user to SYSTEM level. The vulnerability does not require user interaction and can be triggered remotely only if local access is obtained, making it a local privilege escalation vector. The CVSS v3.1 base score is 9.9, reflecting critical severity with network attack vector, low attack complexity, and high impact on confidentiality, integrity, and availability. No public exploits have been reported yet, but the vulnerability’s nature and criticality suggest it could be targeted soon. The lack of a patch at the time of disclosure increases the urgency for defensive measures. The affected versions include all Avast Antivirus editions before 25.3 on Windows, which are widely used in both consumer and enterprise environments. The vulnerability’s exploitation could allow attackers to bypass sandbox protections, compromise endpoint security, and potentially move laterally within networks.

For European organizations, the impact of CVE-2025-13032 is significant due to the widespread use of Avast Antivirus on Windows endpoints across enterprises, government agencies, and critical infrastructure sectors. Successful exploitation would grant attackers SYSTEM-level privileges, enabling full control over affected machines. This could lead to unauthorized access to sensitive data, disruption of business operations, deployment of ransomware or other malware, and lateral movement within corporate networks. The critical nature of the vulnerability threatens confidentiality, integrity, and availability of systems. Organizations in sectors such as finance, healthcare, energy, and public administration are particularly at risk due to the sensitive nature of their data and the potential for operational disruption. Additionally, the vulnerability could undermine trust in endpoint security solutions, complicating incident response and recovery efforts. The absence of known exploits currently provides a window for proactive mitigation, but the high severity score indicates that exploitation could have devastating consequences.

1. Immediate implementation of strict local user access controls to minimize the number of users with local login privileges, reducing the attack surface. 2. Monitor and audit kernel driver activity and system logs for unusual or suspicious behavior indicative of exploitation attempts. 3. Employ application whitelisting and endpoint detection and response (EDR) solutions to detect and block unauthorized privilege escalation attempts. 4. Once available, promptly apply official patches or updates from Avast to remediate the vulnerability. 5. In the interim, consider disabling or restricting the Avast sandbox kernel driver if feasible without compromising endpoint protection, after thorough testing. 6. Educate IT and security teams about the vulnerability specifics to enhance detection and response capabilities. 7. Conduct vulnerability scanning and penetration testing focused on privilege escalation vectors to identify potential exploitation paths. 8. Maintain robust backup and recovery procedures to mitigate impact in case of successful exploitation. 9. Coordinate with Avast support and threat intelligence providers for updates and indicators of compromise related to this vulnerability.