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CVE-2026-45635 Microsoft CVE debrief

CVE-2026-45635 is a HIGH severity vulnerability in Microsoft Windows. A use after free vulnerability in Universal Plug and Play (upnp.dll) allows an attacker to execute code over a network. The vulnerability has a CVSS score of 8.1 and was published on 2026-06-09T17:17:30.100Z. The vulnerability affects multiple versions of Microsoft Windows, including Windows 10, Windows 11, and Windows Server.

Vendor
Microsoft
Product
Windows
CVSS
HIGH 8.1
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-09
Original CVE updated
2026-06-11
Advisory published
2026-06-09
Advisory updated
2026-06-11

Who should care

Administrators and users of Microsoft Windows, particularly those with exposure to Universal Plug and Play (UPnP) functionality, should be aware of this vulnerability.

Technical summary

The vulnerability is a use after free issue in the upnp.dll component of Microsoft Windows. This type of vulnerability occurs when a program uses memory after it has been freed, allowing an attacker to potentially execute arbitrary code.

Defensive priority

HIGH

Recommended defensive actions

  • Apply patches from Microsoft as soon as possible, particularly for systems exposed to UPnP functionality.
  • Review and limit exposure to UPnP if not required.
  • Monitor network traffic for suspicious activity related to UPnP.

Evidence notes

The CVE record and NVD detail pages provide comprehensive information about the vulnerability, including affected versions and potential mitigations.

Official resources

CVE-2026-45635 was published on 2026-06-09T17:17:30.100Z and modified on 2026-06-11T18:36:06.110Z.