CVE-2025-33073
Microsoft Windows SMB Client Improper Access Control Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 10 November 2025). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
Description
Improper access control in Windows SMB allows an authorized attacker to elevate privileges over a network.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 82.70% probability · 100th percentile
- Public exploits
- 1 in Exploit-DB · first 15 June 2025
- CISA KEV
- Listed 20 October 2025 · due 10 November 2025
- Weakness
- CWE-284
- Affected
- microsoft/windows 10 1507 · microsoft/windows 10 1607 · microsoft/windows 10 1809 · microsoft/windows 10 21h2 · microsoft/windows 10 22h2 · microsoft/windows 11 22h2 · microsoft/windows 11 23h2 · microsoft/windows 11 24h2 · microsoft/windows server 2008 · microsoft/windows server 2012 · microsoft/windows server 2016 · microsoft/windows server 2019 · microsoft/windows server 2022 · microsoft/windows server 2022 23h2 · microsoft/windows server 2025
- Source
- secure@microsoft.com
EPSS 82.7% since 30 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
CISA notes
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. https://msrc.microsoft.com/update-guide/en-US/advisory/CVE-2025-33073 ; https://nvd.nist.gov/vuln/detail/CVE-2025-33073
Public exploits (1)
Entries in Exploit-DB that cite this CVE. Links go to the Exploit-DB page and to the file in the public repository; nothing is hosted here. A verified tick means the Exploit-DB team confirmed the exploit works against the stated version.
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-33073Vendor Advisory
- https://www.vicarius.io/vsociety/posts/cve-2025-33073-detection-script-improper-access-control-in-windows-smb-affects-microsoft-productsThird Party Advisory
- https://www.vicarius.io/vsociety/posts/cve-2025-33073-mitigation-script-improper-access-control-in-windows-smb-affects-microsoft-productsMitigation, Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-33073US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.