Created
February 26, 2019 12:26
-
-
Save fox-srt/6761b07f6fe7b8648de2debe5491c044 to your computer and use it in GitHub Desktop.
IDS Signature to detect the extraneous space in Cobalt Strike < 3.13
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| alert tcp any any -> any any (msg:"FOX-IT - Trojan - Possible CobaltStrike C2 Server"; \ | |
| flow:to_client; \ | |
| content:"HTTP/1.1 200 OK |0d0a|"; fast_pattern; depth:18; \ | |
| content:"Date: "; \ | |
| pcre:"/^HTTP/1.1 200 OK \r\nContent-Type: [^\r\n]{0,100}\r\nDate: [^\r\n]{0,100} GMT\r\n(Content-Length: \d+\r\n)\r\n/"; \ | |
| threshold:type limit, track by_dst, count 1, seconds 600; \ | |
| classtype:trojan-activity; priority:2; \ | |
| sid:21002217; rev:3;) |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Full blog post here: https://blog.fox-it.com/2019/02/26/identifying-cobalt-strike-team-servers-in-the-wild/