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Support #7989

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Impossible to disable some rules.

Added by François RAPIN about 16 hours ago. Updated about 15 hours ago.

Status:
Feedback
Priority:
Normal
Assignee:
-
Affected Versions:
Label:

Description

Hi,

I’m under trixie and I have just migrated to suricata 8.0.1.
suricata-update version is 1.3.7dev0

I would like to disable rule 3321379 and drop all rules that have a technical mitre id.
For this, I modified these 2 files:

disable.conf
3321379 # Many TLS Client + Server Hello - Possible Active Scanning activity and / or random TLS impersonation - T1595

drop.conf
re:mitre_technique_id # Référentiel MITRE ATT&CK

Unfortunately, as you can see here, this rule is still active.

drop tls any any -> any any (msg:" Many TLS Client + Server Hello - Possible Active Scanning activity and / or random TLS impersonation - T1595"; flow:to_client, stateless; threshold: type threshold, track by_both, count 50, seconds 10; flowbits:set,pptrls.manytlsch; flowbits:isnotset,pptrls.manytlsch; content:"|16 03 03|"; startswith; fast_pattern; content:"|02|"; distance:2; reference:url,https://attack.mitre.org/techniques/T1595/; metadata:attack_target Client_and_Server, signature_severity Major, mitre_tactic_id TA0043, mitre_tactic_name Reconnaissance, mitre_technique_id T1595, mitre_technique_name Active_Scanning, created_at 2024_10_15, updated_at 2024_10_15; noalert; sid:3321379; rev:2; classtype:network-scan;)

I know that the order of processing rules is:
disable.conf -> enable.conf -> drop.conf -> modify.conf

So I added unsuccessfully in the modify.conf file:
3321379 "^alert" "# alert" # Many TLS Client + Server Hello - Possible Active Scanning activity and / or random TLS impersonation - T1595
3321379 "^drop" "# drop" # Many TLS Client + Server Hello - Possible Active Scanning activity and / or random TLS impersonation - T1595

Could-you help me to disable rule 3321379 and drop all rules that have a technical miter id?

Small clarification: I have a lot of lines in these 4 configuration files. Everything works fine except for a few rules that are both in disable.conf and that have a drop.conf condition.

Thank you in advance.
Regards,

François,

Actions #1

Updated by Jason Ish about 16 hours ago

Its a dependency on another rule that you have no disabled, so it comes back. 3321378 has flowbits:isset,pptrls.manytlsch; which makes it depend on 3321379 to work properly. So if you disable both of those SIDs you'll get the behaviour you want. This should still work with your drop.conf as modifications made due to a drop.conf configuration do not re-enabled the rules.

Actions #2

Updated by Jason Ish about 16 hours ago

  • Status changed from New to Feedback
Actions #3

Updated by François RAPIN about 15 hours ago

Wow, I was way off the mark. I tested it, and it works fine just by specifying these two rules in the disable.conf file.
Thank you very much for your responsiveness.

Regards,

François

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