CVE-2025-33073: Microsoft Windows SMB Client Improper Access Control Vulnerability

CISA Known Exploited Vulnerability (KEV)

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 (CISA)

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

Weakness behind it

CISA records this vulnerability as an instance of CWE-284. From there the chain continues into CAPEC attack patterns and ATT&CK techniques, all inside this corpus.

References

• NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-33073
• KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog