Microsoft Windows SMB Client Improper Access Control Vulnerability
Microsoft — Windows
- Added to KEV catalog
- 20 October 2025
- Federal remediation due date
- 10 November 2025
- Weakness classification (CWE)
- CWE-284
CISA Description
Microsoft Windows SMB Client contains an improper access control vulnerability that could allow for privilege escalation. An attacker could execute a specially crafted malicious script to coerce the victim machine to connect back to the attack system using SMB and authenticate.
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Notes
https://msrc.microsoft.com/update-guide/en-US/advisory/CVE-2025-33073 ; https://nvd.nist.gov/vuln/detail/CVE-2025-33073
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