1 #--------------------------------------------------
2 # http://www.snort.org Snort Ruleset
3 # Contact: snort-sigs@lists.sourceforge.net
4 #--------------------------------------------------
7 ###################################################
8 # This file contains a sample snort configuration.
9 # You should take the following steps to create your own custom configuration:
11 # 1) Set the network variables.
12 # 2) Configure the decoder
13 # 3) Configure the base detection engine
14 # 4) Configure dynamic loaded libraries
15 # 5) Configure preprocessors
16 # 6) Configure output plugins
17 # 7) Customize your rule set
18 # 8) Customize preprocessor and decoder rule set
19 # 9) Customize shared object rule set
20 ###################################################
22 ###################################################
23 # Step #1: Set the network variables. For more information, see README.variables
24 ###################################################
26 include /etc/snort/vars
28 # Setup the network addresses you are protecting
29 # taken from /etc/snort vars
32 # Set up the external network addresses. A good start may be "any"
35 # List of DNS servers on your network
36 # taken from /etc/snort vars
37 #var DNS_SERVERS $HOME_NET
39 # List of SMTP servers on your network
40 var SMTP_SERVERS $HOME_NET
42 # List of web servers on your network
43 var HTTP_SERVERS $HOME_NET
45 # List of sql servers on your network
46 var SQL_SERVERS $HOME_NET
48 # List of telnet servers on your network
49 var TELNET_SERVERS $HOME_NET
51 # List of ssh servers on your network
52 var SSH_SERVERS $HOME_NET
54 # List of ports you run web servers on
55 portvar HTTP_PORTS [80,311,591,593,901,1220,1414,1830,2301,2381,2809,3128,3702,5250,7001,7777,7779,8000,8008,8028,8080,8088,8118,8123,8180,8243,8280,8888,9090,9091,9443,9999,11371]
57 # List of ports you want to look for SHELLCODE on.
58 portvar SHELLCODE_PORTS !80
60 # List of ports you might see oracle attacks on
61 portvar ORACLE_PORTS 1024:
63 portvar SSH_PORTS [22,222]
64 # other variables, these should not be modified
65 var AIM_SERVERS [64.12.24.0/23,64.12.28.0/23,64.12.161.0/24,64.12.163.0/24,64.12.200.0/24,205.188.3.0/24,205.188.5.0/24,205.188.7.0/24,205.188.9.0/24,205.188.153.0/24,205.188.179.0/24,205.188.248.0/24]
67 # Path to your rules files (this can be a relative path)
68 # Note for Windows users: You are advised to make this an absolute path,
69 # such as: c:\snort\rules
70 var RULE_PATH /etc/snort/rules
71 var SO_RULE_PATH /etc/snort/so_rules
72 var PREPROC_RULE_PATH /etc/snort/preproc_rules
74 ###################################################
75 # Step #2: Configure the decoder. For more information, see README.decode
76 ###################################################
78 # Stop generic decode events:
79 config disable_decode_alerts
81 # Stop Alerts on experimental TCP options
82 config disable_tcpopt_experimental_alerts
84 # Stop Alerts on obsolete TCP options
85 config disable_tcpopt_obsolete_alerts
87 # Stop Alerts on T/TCP alerts
88 #config disable_tcpopt_ttcp_alerts
90 # Stop Alerts on all other TCPOption type events:
91 config disable_tcpopt_alerts
93 # Stop Alerts on invalid ip options
94 #config disable_ipopt_alerts
96 # Alert if value in length field (IP, TCP, UDP) is greater th elength of the packet
97 # config enable_decode_oversized_alerts
99 # Same as above, but drop packet if in Inline mode (requires enable_decode_oversized_alerts)
100 # config enable_decode_oversized_drops
102 # Configure IP / TCP checksum mode
103 config checksum_mode: all
105 # Configure maximum number of flowbit references. For more information, see README.flowbits
106 # config flowbits_size: 64
108 # Configure ports to ignore
109 # config ignore_ports: tcp 21 6667:6671 1356
110 # config ignore_ports: udp 1:17 53
112 # Configure active response for non inline operation. For more information, see REAMDE.active
113 # config response: eth0 attempts 2
114 ###################################################
115 # Step #3: Configure the base detection engine. For more information, see README.decode
116 ###################################################
118 # Configure PCRE match limitations
119 config pcre_match_limit: 3500
120 config pcre_match_limit_recursion: 1500
122 # Configure the detection engine See the Snort Manual, Configuring Snort - Includes - Config
123 config detection: search-method ac-split search-optimize max-pattern-len 20
125 # Configure the event queue. For more information, see README.event_queue
126 config event_queue: max_queue 8 log 3 order_events content_length
128 ###################################################
129 # Per packet and rule latency enforcement
130 # For more information see README.ppm
131 ###################################################
133 # Per Packet latency configuration
134 #config ppm: max-pkt-time 250, \
135 # fastpath-expensive-packets, \
138 # Per Rule latency configuration
139 #config ppm: max-rule-time 200, \
141 # suspend-expensive-rules, \
142 # suspend-timeout 20, \
145 ###################################################
146 # Configure Perf Profiling for debugging
147 # For more information see README.PerfProfiling
148 ###################################################
150 #config profile_rules: print all, sort avg_ticks
151 #config profile_preprocs: print all, sort avg_ticks
152 ###################################################
153 # Step #4: Configure dynamic loaded libraries.
154 # For more information, see Snort Manual, Configuring Snort - Dynamic Modules
155 ###################################################
157 # path to dynamic preprocessor libraries
158 dynamicpreprocessor directory /usr/lib/snort_dynamicpreprocessor/
160 # path to base preprocessor engine
161 dynamicengine /usr/lib/snort_dynamicengine/libsf_engine.so
163 # path to dynamic rules libraries
164 # dynamicdetection directory /usr/lib/snort_dynamicrules
166 ###################################################
167 # Step #5: Configure preprocessors
168 # For more information, see the Snort Manual, Configuring Snort - Preprocessors
169 ###################################################
171 # Inline packet normalization. For more information, see README.normalize
172 # Does nothing in IDS mode
173 preprocessor normalize_ip4
174 preprocessor normalize_tcp: ips ecn stream
175 preprocessor normalize_icmp4
177 # Target-based IP defragmentation. For more inforation, see README.frag3
178 preprocessor frag3_global: max_frags 65536
179 preprocessor frag3_engine: policy windows detect_anomalies overlap_limit 10 min_fragment_length 100 timeout 180
181 # Target-Based stateful inspection/stream reassembly. For more inforation, see README.stream5
182 preprocessor stream5_global: max_tcp 8192, track_tcp yes, track_udp yes, track_icmp no max_active_responses 2 min_response_seconds 5
184 preprocessor stream5_tcp: policy windows, detect_anomalies, require_3whs 180, \
185 overlap_limit 10, small_segments 3 bytes 150, timeout 180, \
186 ports client 21 22 23 25 42 53 79 109 110 111 113 119 135 136 137 139 143 \
187 161 445 513 514 587 593 691 1433 1521 2100 3306 6070 6665 6666 6667 6668 6669 \
188 7000 32770 32771 32772 32773 32774 32775 32776 32777 32778 32779, \
189 ports both 80 311 443 465 563 591 593 636 901 989 992 993 994 995 1220 1414 1830 2301 2381 2809 3128 3702 5250 6907 7001 7702 7777 7779 \
190 7801 7900 7901 7902 7903 7904 7905 7906 7908 7909 7910 7911 7912 7913 7914 7915 7916 \
191 7917 7918 7919 7920 8000 8008 8028 8080 8088 8118 8123 8180 8243 8280 8888 9090 9091 9443 9999 11371
192 preprocessor stream5_udp: timeout 180
194 # performance statistics. For more information, see the Snort Manual, Configuring Snort - Preprocessors - Performance Monitor
195 # preprocessor perfmonitor: time 300 file /var/snort/snort.stats pktcnt 10000
197 # HTTP normalization and anomaly detection. For more information, see README.http_inspect
198 preprocessor http_inspect: global iis_unicode_map unicode.map 1252 compress_depth 20480 decompress_depth 20480
200 preprocessor http_inspect_server: server default \
201 chunk_length 500000 \
202 server_flow_depth 0 \
203 client_flow_depth 0 \
205 oversize_dir_length 500 \
206 max_header_length 750 \
208 ports { 80 311 591 593 901 1220 1414 1830 2301 2381 2809 3128 3702 5250 7001 7777 7779 8000 8008 8028 8080 8088 8118 8123 8180 8243 8280 8888 9090 9091 9443 9999 11371 } \
209 non_rfc_char { 0x00 0x01 0x02 0x03 0x04 0x05 0x06 0x07 } \
211 extended_response_inspection \
214 unlimited_decompress \
215 apache_whitespace no \
229 # ONC-RPC normalization and anomaly detection. For more information, see the Snort Manual, Configuring Snort - Preprocessors - RPC Decode
230 preprocessor rpc_decode: 111 32770 32771 32772 32773 32774 32775 32776 32777 32778 32779 no_alert_multiple_requests no_alert_large_fragments no_alert_incomplete
232 # Back Orifice detection.
235 # FTP / Telnet normalization and anomaly detection. For more information, see README.ftptelnet
236 preprocessor ftp_telnet: global inspection_type stateful encrypted_traffic no
238 preprocessor ftp_telnet_protocol: telnet \
239 ayt_attack_thresh 20 \
240 normalize ports { 23 } \
243 preprocessor ftp_telnet_protocol: ftp server default \
244 def_max_param_len 100 \
245 ports { 21 2100 3535 } \
247 ignore_telnet_erase_cmds yes \
248 ftp_cmds { ABOR ACCT ADAT ALLO APPE AUTH CCC CDUP } \
249 ftp_cmds { CEL CLNT CMD CONF CWD DELE ENC EPRT } \
250 ftp_cmds { EPSV ESTA ESTP FEAT HELP LANG LIST LPRT } \
251 ftp_cmds { LPSV MACB MAIL MDTM MIC MKD MLSD MLST } \
252 ftp_cmds { MODE NLST NOOP OPTS PASS PASV PBSZ PORT } \
253 ftp_cmds { PROT PWD QUIT REIN REST RETR RMD RNFR } \
254 ftp_cmds { RNTO SDUP SITE SIZE SMNT STAT STOR STOU } \
255 ftp_cmds { STRU SYST TEST TYPE USER XCUP XCRC XCWD } \
256 ftp_cmds { XMAS XMD5 XMKD XPWD XRCP XRMD XRSQ XSEM } \
257 ftp_cmds { XSEN XSHA1 XSHA256 } \
258 alt_max_param_len 0 { ABOR CCC CDUP ESTA FEAT LPSV NOOP PASV PWD QUIT REIN STOU SYST XCUP XPWD } \
259 alt_max_param_len 200 { ALLO APPE CMD HELP NLST RETR RNFR STOR STOU XMKD } \
260 alt_max_param_len 256 { CWD RNTO } \
261 alt_max_param_len 400 { PORT } \
262 alt_max_param_len 512 { SIZE } \
263 chk_str_fmt { ACCT ADAT ALLO APPE AUTH CEL CLNT CMD } \
264 chk_str_fmt { CONF CWD DELE ENC EPRT EPSV ESTP HELP } \
265 chk_str_fmt { LANG LIST LPRT MACB MAIL MDTM MIC MKD } \
266 chk_str_fmt { MLSD MLST MODE NLST OPTS PASS PBSZ PORT } \
267 chk_str_fmt { PROT REST RETR RMD RNFR RNTO SDUP SITE } \
268 chk_str_fmt { SIZE SMNT STAT STOR STRU TEST TYPE USER } \
269 chk_str_fmt { XCRC XCWD XMAS XMD5 XMKD XRCP XRMD XRSQ } \
270 chk_str_fmt { XSEM XSEN XSHA1 XSHA256 } \
271 cmd_validity ALLO < int [ char R int ] > \
272 cmd_validity EPSV < [ { char 12 | char A char L char L } ] > \
273 cmd_validity MACB < string > \
274 cmd_validity MDTM < [ date nnnnnnnnnnnnnn[.n[n[n]]] ] string > \
275 cmd_validity MODE < char ASBCZ > \
276 cmd_validity PORT < host_port > \
277 cmd_validity PROT < char CSEP > \
278 cmd_validity STRU < char FRPO [ string ] > \
279 cmd_validity TYPE < { char AE [ char NTC ] | char I | char L [ number ] } >
281 preprocessor ftp_telnet_protocol: ftp client default \
284 ignore_telnet_erase_cmds yes \
287 # SMTP normalization and anomaly detection. For more information, see README.SMTP
288 preprocessor smtp: ports { 25 465 587 691 } \
289 inspection_type stateful \
290 enable_mime_decoding \
291 max_mime_depth 20480 \
293 normalize_cmds { ATRN AUTH BDAT CHUNKING DATA DEBUG EHLO EMAL ESAM ESND ESOM ETRN EVFY } \
294 normalize_cmds { EXPN HELO HELP IDENT MAIL NOOP ONEX QUEU QUIT RCPT RSET SAML SEND SOML } \
295 normalize_cmds { STARTTLS TICK TIME TURN TURNME VERB VRFY X-ADAT X-DRCP X-ERCP X-EXCH50 } \
296 normalize_cmds { X-EXPS X-LINK2STATE XADR XAUTH XCIR XEXCH50 XGEN XLICENSE XQUE XSTA XTRN XUSR } \
297 max_command_line_len 512 \
298 max_header_line_len 1000 \
299 max_response_line_len 512 \
300 alt_max_command_line_len 260 { MAIL } \
301 alt_max_command_line_len 300 { RCPT } \
302 alt_max_command_line_len 500 { HELP HELO ETRN EHLO } \
303 alt_max_command_line_len 255 { EXPN VRFY ATRN SIZE BDAT DEBUG EMAL ESAM ESND ESOM EVFY IDENT NOOP RSET } \
304 alt_max_command_line_len 246 { SEND SAML SOML AUTH TURN ETRN DATA RSET QUIT ONEX QUEU STARTTLS TICK TIME TURNME VERB X-EXPS X-LINK2STATE XADR XAUTH XCIR XEXCH50 XGEN XLICENSE XQUE XSTA XTRN XUSR } \
305 valid_cmds { ATRN AUTH BDAT CHUNKING DATA DEBUG EHLO EMAL ESAM ESND ESOM ETRN EVFY } \
306 valid_cmds { EXPN HELO HELP IDENT MAIL NOOP ONEX QUEU QUIT RCPT RSET SAML SEND SOML } \
307 valid_cmds { STARTTLS TICK TIME TURN TURNME VERB VRFY X-ADAT X-DRCP X-ERCP X-EXCH50 } \
308 valid_cmds { X-EXPS X-LINK2STATE XADR XAUTH XCIR XEXCH50 XGEN XLICENSE XQUE XSTA XTRN XUSR } \
309 xlink2state { enabled }
311 # Portscan detection. For more information, see README.sfportscan
312 preprocessor sfportscan: proto { all } memcap { 10000000 } sense_level { medium }
314 # ARP spoof detection. For more information, see the Snort Manual - Configuring Snort - Preprocessors - ARP Spoof Preprocessor
315 # preprocessor arpspoof
316 # preprocessor arpspoof_detect_host: 192.168.40.1 f0:0f:00:f0:0f:00
318 # SSH anomaly detection. For more information, see README.ssh
319 preprocessor ssh: server_ports { 22 222 } \
321 max_client_bytes 19600 \
322 max_encrypted_packets 20 \
323 max_server_version_len 100 \
324 enable_respoverflow enable_ssh1crc32 \
325 enable_srvoverflow enable_protomismatch
327 # SMB / DCE-RPC normalization and anomaly detection. For more information, see README.dcerpc2
328 preprocessor dcerpc2: memcap 102400, events [co ]
329 preprocessor dcerpc2_server: default, policy WinXP, \
330 detect [smb [139,445], tcp 135, udp 135, rpc-over-http-server 593], \
331 autodetect [tcp 1025:, udp 1025:, rpc-over-http-server 1025:], \
334 # DNS anomaly detection. For more information, see README.dns
335 preprocessor dns: ports { 53 } enable_rdata_overflow
337 # SSL anomaly detection and traffic bypass. For more information, see README.ssl
338 preprocessor ssl: ports { 443 444 465 563 636 989 992 993 994 995 7801 7702 7900 7901 7902 7903 7904 7905 7906 6907 7908 7909 7910 7911 7912 7913 7914 7915 7916 7917 7918 7919 7920 }, trustservers, noinspect_encrypted
340 # SDF sensitive data preprocessor. For more information see README.sensitive_data
341 preprocessor sensitive_data: alert_threshold 25
343 ###################################################
344 # Step #6: Configure output plugins
345 # For more information, see Snort Manual, Configuring Snort - Output Modules
346 ###################################################
349 # Recommended for most installs
350 # output unified2: filename merged.log, limit 128, nostamp, mpls_event_types, vlan_event_types
352 # Additional configuration for specific types of installs
353 # output alert_unified2: filename snort.alert, limit 128, nostamp
354 # output log_unified2: filename snort.log, limit 128, nostamp
356 # output alert_syslog: LOG_AUTH LOG_ALERT
359 # output log_tcpdump: tcpdump.log
362 # output database: alert, <db_type>, user=<username> password=<password> test dbname=<name> host=<hostname>
363 # output database: log, <db_type>, user=<username> password=<password> test dbname=<name> host=<hostname>
366 # output alert_prelude
368 # metadata reference data. do not modify these lines
369 include /etc/snort/rules/classification.config
370 include /etc/snort/rules/reference.config
373 ###################################################
374 # Step #7: Customize your rule set
375 # For more information, see Snort Manual, Writing Snort Rules
376 ###################################################
378 # site specific rules