www.cisa.gov Open in urlscan Pro
2a02:26f0:3500:891::447a  Public Scan

Submitted URL: https://www.cisa.gov/uscert/ncas/current-activity/2017/01/16/SMB-Security-Best-Practices
Effective URL: https://www.cisa.gov/news-events/alerts/2017/01/16/smb-security-best-practices
Submission: On August 27 via api from US — Scanned from DE

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Alert


SMB SECURITY BEST PRACTICES

Last Revised
March 16, 2017


In response to public reporting of a potential Server Message Block (SMB)
vulnerability, US-CERT is providing known best practices related to SMB. This
service is universally available for Windows systems, and legacy versions of SMB
protocols could allow a remote attacker to obtain sensitive information from
affected systems.

US-CERT recommends that users and administrators consider:

 * disabling SMBv1 and
 * blocking all versions of SMB at the network boundary by blocking TCP port 445
   with related protocols on UDP ports 137-138 and TCP port 139, for all
   boundary devices.

US-CERT cautions users and administrators that disabling or blocking SMB may
create problems by obstructing access to shared files, data, or devices. The
benefits of mitigation should be weighed against potential disruptions to users.
For more information on SMB, please review Microsoft Security Advisories
2696547(link is external) and 204279(link is external).

This product is provided subject to this Notification and this Privacy &
Use policy.


PLEASE SHARE YOUR THOUGHTS

We recently updated our anonymous product survey; we’d welcome your feedback.


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CISA RELEASES FOUR INDUSTRIAL CONTROL SYSTEMS ADVISORIES

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