Normalize SMB3 negotiate capability advertisement#2188
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Summary
This PR updates SMB3 negotiate context handling and capability advertisement behavior to better normalize SMB session negotiation.
Changes
ClientGuidand SMB3 preauth integrity behavior unchangedSMB2EncryptionCapabilitiesbehavior (self.EncryptionAlgorithmList = ['AES-CCM']) as a recognizable characteristic/IoC for defendersNotes
Based on review feedback, the earlier
ClientGuidand SMB3 preauth integrity randomization changes were reverted and intentionally left out of this PR, since those defaults can still serve as useful IoCs for defenders.I also intentionally kept the existing
SMB2EncryptionCapabilities/EncryptionAlgorithmListbehavior unchanged for the same reason.The remaining changes are intended to focus strictly on SMB negotiation behavior and protocol handling rather than detection evasion.
Also, thanks again for the excellent Impacket-IoCs project — it was genuinely very helpful while researching and understanding many of these SMB negotiation behaviors and implementation fingerprints.
Happy to contribute back to Impacket, even in a small way.