CVE-2025-21276

Summary

CVE-2025-21276 is a newly disclosed vulnerability affecting Windows systems. This Denial of Service (DoS) issue lies in the MapUrlToZone function, which is responsible for mapping URLs to security zones. An attacker can exploit this vulnerability by sending specially crafted URLs to a targeted system, resulting in an excessive consumption of system resources. As a consequence, the victim's system may experience degraded performance or even become unresponsive, rendering it inaccessible for legitimate users. Microsoft released a security advisory and a patch to address this vulnerability. It is highly recommended for Windows users to apply the patch promptly to mitigate the risk of potential attacks.

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