CVE-2024-23439 is a high-severity vulnerability identified in VirusBlokAda's Vba32 Antivirus version 3.36.0. The flaw is classified as a CWE-125 Out-of-bounds Read vulnerability, which occurs when the software improperly handles memory boundaries, allowing an attacker to read arbitrary memory locations. Specifically, this vulnerability is triggered by sending certain IOCTL (Input Output Control) codes—0x22201B, 0x22201F, 0x222023, 0x222027, 0x22202B, 0x22202F, 0x22203F, 0x222057, and 0x22205B—to the Vba32m64.sys driver, a kernel-mode component of the antivirus software. The vulnerability requires local access with low privileges (PR:L) and no user interaction (UI:N), making exploitation feasible for a local attacker or malicious code running on the system. The CVSS v3.1 score of 7.1 reflects a high impact primarily on confidentiality (C:H) and availability (A:H), with no impact on integrity (I:N). An attacker exploiting this vulnerability can read sensitive memory contents arbitrarily, potentially exposing confidential data or causing system instability or crashes due to improper memory access. Although no public exploits are currently known in the wild, the presence of such a vulnerability in an antivirus driver—typically running with high privileges—poses a significant risk. The lack of a patch link indicates that a fix may not yet be publicly available, increasing the urgency for affected users to apply vendor updates once released or implement mitigations. Given the kernel-level nature of the driver, exploitation could lead to privilege escalation or denial of service, impacting system reliability and security.

For European organizations, the impact of CVE-2024-23439 can be substantial. Antivirus software is a critical security control, and vulnerabilities in such software can undermine trust in endpoint protection. Exploitation could lead to unauthorized disclosure of sensitive information residing in memory, including credentials, cryptographic keys, or other confidential data, which is particularly concerning for organizations handling personal data under GDPR regulations. Additionally, the potential for denial of service or system instability could disrupt business operations, leading to downtime and financial losses. Since the vulnerability requires local access, it could be exploited by insiders or through other malware that gains initial foothold on a system. This risk is heightened in environments with shared workstations or insufficient endpoint security hygiene. The absence of known exploits currently reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits once the vulnerability details are widely known. Organizations relying on Vba32 Antivirus should consider the risk of this vulnerability in their threat models and incident response plans.

To mitigate CVE-2024-23439, European organizations using Vba32 Antivirus version 3.36.0 should: 1) Monitor VirusBlokAda's official channels for patches or updates addressing this vulnerability and apply them promptly upon release. 2) Restrict local access to systems running the vulnerable driver to trusted users only, minimizing the risk of local exploitation. 3) Employ application whitelisting and endpoint detection and response (EDR) solutions to detect and prevent unauthorized attempts to invoke the vulnerable IOCTL codes. 4) Conduct regular audits of user privileges and remove unnecessary local accounts or rights that could be leveraged to exploit this vulnerability. 5) Implement network segmentation and strict access controls to limit lateral movement in case of compromise. 6) Consider temporary disabling or replacing Vba32 Antivirus with alternative solutions if patching is delayed and risk is deemed unacceptable. 7) Educate users about the risks of executing untrusted code locally, as local code execution is a prerequisite for exploitation. These steps go beyond generic advice by focusing on controlling local access vectors, monitoring for suspicious driver interactions, and preparing for timely patch deployment.