CVE-2026-24796 identifies an out-of-bounds read vulnerability (CWE-125) in the CloverHackyColor CloverBootloader, a popular bootloader used primarily in Hackintosh environments to enable macOS to run on non-Apple hardware. The vulnerability resides in the Oniguruma regular expression modules within the MdeModulePkg/Universal/RegularExpressionDxe component, specifically in the regparse.C program files. An out-of-bounds read occurs when the software reads memory outside the allocated buffer, which can lead to information disclosure or cause undefined behavior. The flaw affects all versions of CloverBootloader before build 5162. Exploitation requires local access (AV:L), but no privileges (PR:N) or user interaction (UI:N) are needed, making it a low-complexity attack vector. The vulnerability does not impact confidentiality fully (R:U) but has a high impact on availability (VA:H) due to potential memory corruption side effects. No known public exploits exist yet, and no patches have been linked, indicating the need for vigilance and prompt updates once fixes are released. The vulnerability is significant in environments where CloverBootloader is used to manage boot processes, as it could allow attackers to read sensitive memory areas, potentially exposing cryptographic keys or other critical data during system startup.

For European organizations, the primary impact of CVE-2026-24796 lies in the potential unauthorized disclosure of sensitive information during the boot process. Since CloverBootloader is commonly used in Hackintosh setups and some custom macOS deployments, organizations relying on such systems for development, testing, or specialized workflows could face confidentiality risks. The vulnerability could be exploited by an attacker with local access to extract memory contents, potentially exposing credentials, encryption keys, or proprietary information. While it does not directly compromise system integrity or availability, the information leakage could facilitate further attacks or unauthorized access. Given the medium severity, the risk is moderate but should not be underestimated, especially in environments with sensitive data or regulatory compliance requirements such as GDPR. The lack of known exploits reduces immediate risk but also means organizations should proactively patch and monitor affected systems to prevent future exploitation.

1. Update CloverBootloader to version 5162 or later as soon as a patched release is available to address the out-of-bounds read vulnerability. 2. Restrict local access to systems running CloverBootloader by enforcing strict physical and logical access controls, including multi-factor authentication and endpoint security measures. 3. Monitor system logs and bootloader behavior for unusual activity that could indicate exploitation attempts. 4. Conduct regular audits of systems using CloverBootloader to identify unauthorized modifications or suspicious processes. 5. For organizations using Hackintosh or custom macOS environments, consider migrating to officially supported hardware and bootloaders to reduce exposure to such vulnerabilities. 6. Implement memory protection mechanisms and secure boot features where possible to limit the impact of bootloader vulnerabilities. 7. Educate IT staff about the risks associated with bootloader vulnerabilities and the importance of timely patching and access control.