CVE-2025-59295 is a heap-based buffer overflow vulnerability classified under CWE-122, affecting Internet Explorer running on Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). This vulnerability arises from improper handling of memory buffers in Internet Explorer, allowing an attacker to overwrite heap memory. Exploitation requires the victim to interact with malicious content, such as visiting a crafted web page or opening a malicious file, enabling remote code execution without any prior authentication. The vulnerability impacts confidentiality, integrity, and availability, as arbitrary code execution can lead to system compromise, data theft, or service disruption. The CVSS 3.1 score of 8.8 reflects a high severity with network attack vector, low attack complexity, no privileges required, but user interaction needed. Although no exploits are currently known in the wild, the presence of this vulnerability in a widely used OS and browser component makes it a significant risk. No official patches have been released yet, but organizations should anticipate updates from Microsoft. The vulnerability's exploitation could be leveraged in targeted attacks or widespread campaigns, especially against organizations relying on legacy Internet Explorer components within Windows 11 environments.

European organizations using Windows 11 Version 25H2 with Internet Explorer are at risk of remote code execution attacks that can lead to full system compromise. This can result in data breaches, disruption of critical services, and potential lateral movement within networks. Sectors such as government, finance, healthcare, and critical infrastructure are particularly vulnerable due to the sensitive nature of their data and operations. The vulnerability's network-based attack vector and lack of required privileges increase the likelihood of exploitation. The requirement for user interaction limits automated exploitation but does not eliminate risk, especially in environments where users frequently access web content or receive external files. The absence of known exploits in the wild currently reduces immediate risk but does not preclude future active exploitation. The impact on confidentiality, integrity, and availability is high, potentially affecting business continuity and regulatory compliance within the EU.

1. Disable Internet Explorer or restrict its use through group policies and application control to minimize exposure. 2. Employ network-level protections such as web filtering, intrusion detection/prevention systems (IDS/IPS), and firewall rules to block access to malicious sites. 3. Educate users about the risks of interacting with untrusted web content or email attachments to reduce the likelihood of triggering the vulnerability. 4. Monitor security advisories from Microsoft closely and apply patches immediately upon release. 5. Use endpoint detection and response (EDR) tools to identify and respond to suspicious activities related to exploitation attempts. 6. Consider deploying application sandboxing or virtualization for legacy applications that require Internet Explorer. 7. Regularly audit and update software inventories to identify systems running the affected Windows 11 build and Internet Explorer components. 8. Implement network segmentation to limit potential lateral movement if a system is compromised.