Snort mailing list archives
Re: Snort 2.8.6 and gzip decoding functionality not working for me
From: Matt Watchinski <mwatchinski () sourcefire com>
Date: Tue, 4 May 2010 16:06:41 -0400
Trying changing your http_inspect config to this for the first line: preprocessor http_inspect: global iis_unicode_map unicode.map 1252 compress_depth 20480 decompress_depth 20480 Cheers, -matt On Tue, May 4, 2010 at 3:40 PM, L0rd Ch0de1m0rt <l0rdch0de1m0rt () gmail com> wrote:
Hello. I am experimenting with snort v2.8.6 and hope to benefit from its gzip decoding capabilities. However, I have been unsuccessful so far in getting it to work. I am fetching a javascript file from google and clearly it is encoding it using gzip. This rule alerts me: alert tcp any any -> any any (msg:"gzip encoding detected from server"; flow:established,from_server; content:"|0d 0a|Content-Encoding: gzip|0d 0a|"; nocase; classtype:attempted-user; sid:3141591; rev:1;) BUT this rule does not alert when it is clearly in the gzip decoded data: alert tcp any any -> any any (msg:"detected on gzip decoded data from Google"; flow:established,from_server; content:"google.isOpera=false"; nocase; classtype:attempted-user; sid:3141592; rev:1;) I am using the defaults for the gzip portion of the http_inspect preprocessor and the content trying to be matched (google.isOpera=false) is in the first few hundred bytes of the data. Here is my snort.conf http_inspect details: preprocessor http_inspect: global iis_unicode_map unicode.map 1252 preprocessor http_inspect_server: server default \ apache_whitespace no \ ascii no \ bare_byte no \ chunk_length 500000 \ server_flow_depth 0 \ client_flow_depth 0 \ post_depth 65495 \ directory no \ double_decode no \ iis_backslash no \ iis_delimiter no \ iis_unicode no \ multi_slash no \ non_strict \ oversize_dir_length 500 \ ports { 80 1220 2301 3128 7777 7779 8000 8008 8028 8080 8180 8888 9999 } \ u_encode yes \ non_rfc_char { 0x00 0x01 0x02 0x03 0x04 0x05 0x06 0x07 } \ webroot no \ extended_response_inspection \ inspect_gzip I configured snort with --enable-zlib before I compiled and I get this on snort startup: Using ZLIB version: 1.2.3.3 What am I doing wrong here? Thanks for any help. Cheers, -L0rd Ch0de1m0rt ------------------------------------------------------------------------------ _______________________________________________ Snort-sigs mailing list Snort-sigs () lists sourceforge net https://lists.sourceforge.net/lists/listinfo/snort-sigs
-- Matthew Watchinski Sr. Director Vulnerability Research Team (VRT) Sourcefire, Inc. Office: 410-423-1928 http://vrt-sourcefire.blogspot.com && http://www.snort.org/vrt/ ------------------------------------------------------------------------------ _______________________________________________ Snort-sigs mailing list Snort-sigs () lists sourceforge net https://lists.sourceforge.net/lists/listinfo/snort-sigs
Current thread:
- Snort 2.8.6 and gzip decoding functionality not working for me L0rd Ch0de1m0rt (May 04)
- Re: Snort 2.8.6 and gzip decoding functionality not working for me Matt Olney (May 04)
- Re: Snort 2.8.6 and gzip decoding functionality not working for me Matt Watchinski (May 04)
- Re: Snort 2.8.6 and gzip decoding functionality not working for me Bhagya Bantwal (May 04)
- Re: Snort 2.8.6 and gzip decoding functionality not working for me L0rd Ch0de1m0rt (May 04)
- Re: Snort 2.8.6 and gzip decoding functionality not working for me Matt Watchinski (May 04)
- Re: Snort 2.8.6 and gzip decoding functionality not working for me L0rd Ch0de1m0rt (May 05)
- Re: Snort 2.8.6 and gzip decoding functionality not working for me Jason Wallace (May 06)
- Re: Snort 2.8.6 and gzip decoding functionality not working for me Matt Olney (May 06)
- Re: Snort 2.8.6 and gzip decoding functionality not working for me Nerijus Krukauskas (May 14)
- Re: Snort 2.8.6 and gzip decoding functionality not working for me L0rd Ch0de1m0rt (May 04)