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MITRE ATT&CK® Mitigation

T1187: Forced Authentication Mitigation

Block SMB traffic from exiting an enterprise network with egress filtering or by blocking TCP ports 139, 445 and UDP port 137. Filter or block WebDAV protocol traffic from exiting the network. If access to external resources over SMB and WebDAV is necessary, then traffic should be tightly limited with whitelisting. [1] [2]

For internal traffic, monitor the workstation-to-workstation unusual (vs. baseline) SMB traffic. For many networks there should not be any, but it depends on how systems on the network are configured and where resources are located.

Use strong passwords to increase the difficulty of credential hashes from being cracked if they are obtained.

EnterpriseT1187MitigationObject v1.0 Modified
Historical object

This ATT&CK object is revoked or deprecated in the current MITRE ATT&CK release.

It remains available for historical context and inbound links. Use current ATT&CK relationships and replacement guidance before basing detection or reporting work on this page.

Glexia's Take

Analyst summary pending validation

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Official MITRE ATT&CK definition

Forced Authentication Mitigation

Block SMB traffic from exiting an enterprise network with egress filtering or by blocking TCP ports 139, 445 and UDP port 137. Filter or block WebDAV protocol traffic from exiting the network. If access to external resources over SMB and WebDAV is necessary, then traffic should be tightly limited with whitelisting. [1] [2]

For internal traffic, monitor the workstation-to-workstation unusual (vs. baseline) SMB traffic. For many networks there should not be any, but it depends on how systems on the network are configured and where resources are located.

Use strong passwords to increase the difficulty of credential hashes from being cracked if they are obtained.

View the same entry on attack.mitre.org (MITRE-hosted reference; in-page links above use the Glexia ATT&CK library.)

Glexia analysis

How security teams should use this page

Treat this object as behavior context, not an attribution claim. Validate the related groups, software, data sources, and mitigations against official ATT&CK relationships and your own telemetry before making control-coverage decisions.

Relationship explorer

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Change history

Object version and sync metadata

The fields below describe the current mirrored snapshot. When Glexia retains multiple ATT&CK source imports, you can open the table to compare the same object across releases (hashes and MITRE timestamps). For MITRE’s own release notes and roadmap, see ATT&CK resources — Updates .

ATT&CK release
19.1
Object version
1.0
Created
Modified
Raw hash
cc15751d9d1db2b6...
Imported snapshots across ATT&CK releases (1)
Release Bundle imported Object version Modified Status Raw hash
19.1 1.0 Current bundle Deprecated cc15751d9d1d…
Raw source

Mirrored ATT&CK source object

The raw object is retained through the mirrored ATT&CK source bundle and object hash. The raw endpoint returns the exact object from the mirrored bundle when available.

Source references

External references and citations

MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.

  1. [1]
    US-CERT SMB Security

    US-CERT. (2017, March 16). SMB Security Best Practices. Retrieved December 21, 2017.

    Open source URL
  2. [2]
    US-CERT APT Energy Oct 2017

    US-CERT. (2017, October 20). Alert (TA17-293A): Advanced Persistent Threat Activity Targeting Energy and Other Critical Infrastructure Sectors. Retrieved November 2, 2017.

    Open source URL
  3. [3]
    mitre-attack T1187
    Open source URL
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