This is a discussion on Re: [Snort-users] not write alert file within the Snort forums, part of the System Security and Security Related category; Just because you have the icmp.rules enabled does not mean you are alerting on every ping request. There is ...
|
|||||||
| FAQ | Members List | Calendar | Search | Today's Posts | Mark Forums Read |
|
|||
|
Just because you have the icmp.rules enabled does not mean you are
alerting on every ping request. There is not a signature in the default icmp.rules file that fires on every ping. > Dear Matt and all the snort user > > thanks to so early to reply. > I'm glad to like it > >>At 03:30 AM 11/14/2003, Hideki Hirata wrote: >>># ping (eth0_address in my server) (enter) >>># ping (same subnet among other host ipaddress ) (enter) >>> >>>/var/log/snort/alert log not write.!! >>>nothing write. >> >>why would pinging your snort box with a normal ping cause an alert?. did >>you add the rules that do this? (by default they are NOT included when >>using the default snort.conf). > > yes.! it was used default snort.conf > > actual file (/etc/snort.conf) > ---------------------------------------------------------------------------- > #-------------------------------------------------- > # http://www.snort.org Snort 2.0.0 Ruleset > # Contact: snort-sigs@lists.sourceforge.net > #-------------------------------------------------- > # $Id: snort.conf,v 1.124 2003/05/16 02:52:41 cazz Exp $ > # > ################################################## # > # This file contains a sample snort configuration. > # You can take the following steps to create your > # own custom configuration: > # > # 1) Set the network variables for your network > # 2) Configure preprocessors > # 3) Configure output plugins > # 4) Customize your rule set > # > ################################################## # > # Step #1: Set the network variables: > # > # You must change the following variables to reflect > # your local network. The variable is currently > # setup for an RFC 1918 address space. > # > # You can specify it explicitly as: > # > # var HOME_NET 10.1.1.0/24 > # > # or use global variable $<interfacename>_ADDRESS > # which will be always initialized to IP address and > # netmask of the network interface which you run > # snort at. Under Windows, this must be specified > # as $(<interfacename>_ADDRESS), such as: > # $(\Device\Packet_{12345678-90AB-CDEF-1234567890AB}_ADDRESS) > # > # var HOME_NET $eth0_ADDRESS > # > # You can specify lists of IP addresses for HOME_NET > # by separating the IPs with commas like this: > # > # var HOME_NET [10.1.1.0/24,192.168.1.0/24] > # > # MAKE SURE YOU DON'T PLACE ANY SPACES IN YOUR LIST! > # > # or you can specify the variable to be any IP address > # like this: > > var HOME_NET any > > # Set up the external network addresses as well. > # A good start may be "any" > > var EXTERNAL_NET any > > # Configure your server lists. This allows snort to only look for attacks > # to systems that have a service up. Why look for HTTP attacks if you are > # not running a web server? This allows quick filtering based on IP > addresses > # These configurations MUST follow the same configuration scheme as > defined > # above for $HOME_NET. > > # List of DNS servers on your network > var DNS_SERVERS $HOME_NET > > # List of SMTP servers on your network > var SMTP_SERVERS $HOME_NET > > # List of web servers on your network > var HTTP_SERVERS $HOME_NET > > # List of sql servers on your network > var SQL_SERVERS $HOME_NET > > # List of telnet servers on your network > var TELNET_SERVERS $HOME_NET > > # Configure your service ports. This allows snort to look for attacks > # destined to a specific application only on the ports that application > # runs on. For example, if you run a web server on port 8081, set your > # HTTP_PORTS variable like this: > # > # var HTTP_PORTS 8081 > # > # Port lists must either be continuous [eg 80:8080], or a single port [eg > 80]. > # We will adding support for a real list of ports in the future. > > # Ports you run web servers on > var HTTP_PORTS 80 > > # Ports you want to look for SHELLCODE on. > var SHELLCODE_PORTS !80 > > # Ports you do oracle attacks on > var ORACLE_PORTS 1521 > > # other variables > # > # AIM servers. AOL has a habit of adding new AIM servers, so instead of > # modifying the signatures when they do, we add them to this list of > # servers. > var AIM_SERVERS > [64.12.24.0/24,64.12.25.0/24,64.12.26.14/24,64.12.28.0/24,64.12. > 29.0/24,64.12.161.0/24,64.12.163.0/24,205.188.5.0/24,205.188.9.0/24] > > # Path to your rules files (this can be a relative path) > var RULE_PATH /etc/snort/rules > > # Configure the snort decoder: > # ============================ > # > # Stop generic decode events: > # > # config disable_decode_alerts > # > # Stop Alerts on experimental TCP options > # > # config disable_tcpopt_experimental_alerts > # > # Stop Alerts on obsolete TCP options > # > # config disable_tcpopt_obsolete_alerts > # > # Stop Alerts on T/TCP alerts > # > # config disable_ttcp_alerts > # > # Stop Alerts on all other TCPOption type events: > # > # config disable_tcpopt_alerts > # > # Stop Alerts on invalid ip options > # > # config disable_ipopt_alerts > > > # Configure the detection engine > # =============================== > # > # Use a different pattern matcher in case you have a machine with very > # limited resources: > # > # config detection: search-method lowmem > > > ################################################## # > # Step #2: Configure preprocessors > # > # General configuration for preprocessors is of > # the form > # preprocessor <name_of_processor>: <configuration_options> > > # frag2: IP defragmentation support > # ------------------------------- > # This preprocessor performs IP defragmentation. This plugin will also > detect > # people launching fragmentation attacks (usually DoS) against hosts. No > # arguments loads the default configuration of the preprocessor, which is > a > # 60 second timeout and a 4MB fragment buffer. > > # The following (comma delimited) options are available for frag2 > # timeout [seconds] - sets the number of [seconds] than an unfinished > # fragment will be kept around waiting for > completion, > # if this time expires the fragment will be flushed > # memcap [bytes] - limit frag2 memory usage to [number] bytes > # (default: 4194304) > # > # min_ttl [number] - minimum ttl to accept > # > # ttl_limit [number] - difference of ttl to accept without alerting > # will cause false positves with router flap > # > # Frag2 uses Generator ID 113 and uses the following SIDS > # for that GID: > # SID Event description > # ----- ------------------- > # 1 Oversized fragment (reassembled frag > 64k bytes) > # 2 Teardrop-type attack > > preprocessor frag2 > > # stream4: stateful inspection/stream reassembly for Snort > #---------------------------------------------------------------------- > # Use in concert with the -z [all|est] command line switch to defeat > # stick/snot against TCP rules. Also performs full TCP stream > # reassembly, stateful inspection of TCP streams, etc. Can statefully > # detect various portscan types, fingerprinting, ECN, etc. > > # stateful inspection directive > # no arguments loads the defaults (timeout 30, memcap 8388608) > # options (options are comma delimited): > # detect_scans - stream4 will detect stealth portscans and generate > alerts > # when it sees them when this option is set > # detect_state_problems - detect TCP state problems, this tends to be > very > # noisy because there are a lot of crappy ip > stack > # implementations out there > # > # disable_evasion_alerts - turn off the possibly noisy mitigation of > # overlapping sequences. > # > # > # min_ttl [number] - set a minium ttl that snort will accept to > # stream reassembly > # > # ttl_limit [number] - differential of the initial ttl on a session > versus > # the normal that someone may be playing > games. > # Routing flap may cause lots of false > positives. > # > # keepstats [machine|binary] - keep session statistics, add "machine" to > # get them in a flat format for machine reading, > add > # "binary" to get them in a unified binary output > # format > # noinspect - turn off stateful inspection only > # timeout [number] - set the session timeout counter to [number] > seconds, > # default is 30 seconds > # memcap [number] - limit stream4 memory usage to [number] bytes > # log_flushed_streams - if an event is detected on a stream this option > will > # cause all packets that are stored in the stream4 > # packet buffers to be flushed to disk. This only > # works when logging in pcap mode! > # > # Stream4 uses Generator ID 111 and uses the following SIDS > # for that GID: > # SID Event description > # ----- ------------------- > # 1 Stealth activity > # 2 Evasive RST packet > # 3 Evasive TCP packet retransmission > # 4 TCP Window violation > # 5 Data on SYN packet > # 6 Stealth scan: full XMAS > # 7 Stealth scan: SYN-ACK-PSH-URG > # 8 Stealth scan: FIN scan > # 9 Stealth scan: NULL scan > # 10 Stealth scan: NMAP XMAS scan > # 11 Stealth scan: Vecna scan > # 12 Stealth scan: NMAP fingerprint scan stateful detect > # 13 Stealth scan: SYN-FIN scan > # 14 TCP forward overlap > > preprocessor stream4: detect_scans, disable_evasion_alerts > > # tcp stream reassembly directive > # no arguments loads the default configuration > # Only reassemble the client, > # Only reassemble the default list of ports (See below), > # Give alerts for "bad" streams > # > # Available options (comma delimited): > # clientonly - reassemble traffic for the client side of a connection > only > # serveronly - reassemble traffic for the server side of a connection > only > # both - reassemble both sides of a session > # noalerts - turn off alerts from the stream reassembly stage of stream4 > # ports[list] - use the space separated list of ports in[list], "all" > # will turn on reassembly for all ports, "default" will > turn > # on reassembly for ports 21, 23, 25, 53, 80, 143, 110, > 111 > # and 513 > > preprocessor stream4_reassemble > > # http_decode: normalize HTTP requests > # ------------------------------------ > # http_decode normalizes HTTP requests from remote > # machines by converting any %XX character > # substitutions to their ASCII equivalent. This is > # very useful for doing things like defeating hostile > # attackers trying to stealth themselves from IDSs by > # mixing these substitutions in with the request. > # Specify the port numbers you want it to analyze as arguments. > # > # Major code cleanups thanks to rfp > # > # unicode - normalize unicode > # iis_alt_unicode - %u encoding from iis > # double_encode - alert on possible double encodings > # iis_flip_slash - normalize \ as / > # full_whitespace - treat \t as whitespace ( for apache ) > # > # for that GID: > # SID Event description > # ----- ------------------- > # 1 UNICODE attack > # 2 NULL byte attack > > preprocessor http_decode: 80 unicode iis_alt_unicode double_encode > iis_flip_slas > h full_whitespace > > # rpc_decode: normalize RPC traffic > # --------------------------------- > # RPC may be sent in alternate encodings besides the usual > # 4-byte encoding that is used by default. This preprocessor > # normalized RPC traffic in much the same way as the http_decode > # preprocessor. This plugin takes the ports numbers that RPC > # services are running on as arguments. > # The RPC decode preprocessor uses generator ID 106 > # > # arguments: space separated list > # alert_fragments - alert on any rpc fragmented TCP data > # no_alert_multiple_requests - don't alert when >1 rpc query is in a > packet > # no_alert_large_fragments - don't alert when the fragmented > # sizes exceed the current packet size > # no_alert_incomplete - don't alert when a single segment > # exceeds the current packet size > > preprocessor rpc_decode: 111 32771 > > # bo: Back Orifice detector > # ------------------------- > # Detects Back Orifice traffic on the network. Takes no arguments in 2.0. > # > # The Back Orifice detector uses Generator ID 105 and uses the > # following SIDS for that GID: > # SID Event description > # ----- ------------------- > # 1 Back Orifice traffic detected > > preprocessor bo > > # telnet_decode: Telnet negotiation string normalizer > # --------------------------------------------------- > # This preprocessor "normalizes" telnet negotiation strings from > # telnet and ftp traffic. It works in much the same way as the > # http_decode preprocessor, searching for traffic that breaks up > # the normal data stream of a protocol and replacing it with > # a normalized representation of that traffic so that the "content" > # pattern matchingkeyword can work without requiring modifications. > # This preprocessor requires no arguments. > # Portscan uses Generator ID 109 and does not generate any SID currently. > > preprocessor telnet_decode > > # Portscan: detect a variety of portscans > # --------------------------------------- > # portscan preprocessor by Patrick Mullen <p_mullen@linuxrc.net> > # This preprocessor detects UDP packets or TCP SYN packets going to > # four different ports in less than three seconds. "Stealth" TCP > # packets are always detected, regardless of these settings. > # Portscan uses Generator ID 100 and uses the following SIDS for that GID: > # SID Event description > # ----- ------------------- > # 1 Portscan detect > # 2 Inter-scan info > # 3 Portscan End > > # preprocessor portscan: $HOME_NET 4 3 portscan.log > > # Use portscan-ignorehosts to ignore TCP SYN and UDP "scans" from > # specific networks or hosts to reduce false alerts. It is typical > # to see many false alerts from DNS servers so you may want to > # add your DNS servers here. You can all multiple hosts/networks > # in a whitespace-delimited list. > # > #preprocessor portscan-ignorehosts: 0.0.0.0 > > # arpspoof > #---------------------------------------- > # Experimental ARP detection code from Jeff Nathan, detects ARP attacks, > # unicast ARP requests, and specific ARP mapping monitoring. To make use > # of this preprocessor you must specify the IP and hardware address of > hosts on > # the same layer 2 segment as you. Specify one host IP MAC combo per > line. > # Also takes a "-unicast" option to turn on unicast ARP request detection. > # Arpspoof uses Generator ID 112 and uses the following SIDS for that GID: > # SID Event description > # ----- ------------------- > # 1 Unicast ARP request > # 2 Etherframe ARP mismatch (src) > # 3 Etherframe ARP mismatch (dst) > # 4 ARP cache overwrite attack > > #preprocessor arpspoof > #preprocessor arpspoof_detect_host: 192.168.40.1 f0:0f:00:f0:0f:00 > > # Conversation > #------------------------------------------ > # This preprocessor tracks conversations for tcp, udp and icmp traffic. > It > # is a prerequisite for running portscan2. > # > # allowed_ip_protcols 1 6 17 > # list of allowed ip protcols ( defaults to any ) > # > # timeout [num] > # conversation timeout ( defaults to 60 ) > # > # > # max_conversations [num] > # number of conversations to support at once (defaults to 65335) > # > # > # alert_odd_protocols > # alert on protocols not listed in allowed_ip_protocols > # > # preprocessor conversation: allowed_ip_protocols all, timeout 60, > max_conversat > ions 3000 > # > # Portscan2 > #------------------------------------------- > # Portscan 2, detect portscans in a new and exciting way. You must enable > # spp_conversation in order to use this preprocessor. > # > # Available options: > # scanners_max [num] > # targets_max [num] > # target_limit [num] > # port_limit [num] > # timeout [num] > # log [logdir] > # > #preprocessor portscan2: scanners_max 256, targets_max 1024, target_limit > 5, por > t_limit 20, timeout 60 > > # Too many false alerts from portscan2? Tone it down with > # portscan2-ignorehosts! > # > # A space delimited list of addresses in CIDR notation to ignore > # > # preprocessor portscan2-ignorehosts: 10.0.0.0/8 192.168.24.0/24 > # > > # Experimental Perf stats > # ----------------------- > # No docs. Highly subject to change. > # > # preprocessor perfmonitor: console flow events time 10 > > ################################################## ################## > # Step #3: Configure output plugins > # > # Uncomment and configure the output plugins you decide to use. > # General configuration for output plugins is of the form: > # > # output <name_of_plugin>: <configuration_options> > # > # alert_syslog: log alerts to syslog > # ---------------------------------- > # Use one or more syslog facilities as arguments. Win32 can also > # optionally specify a particular hostname/port. Under Win32, the > # default hostname is '127.0.0.1', and the default port is 514. > # > # [Unix flavours should use this format...] > # output alert_syslog: LOG_AUTH LOG_ALERT > # > # [Win32 can use any of these formats...] > # output alert_syslog: LOG_AUTH LOG_ALERT > # output alert_syslog: host=hostname, LOG_AUTH LOG_ALERT > # output alert_syslog: host=hostname:port, LOG_AUTH LOG_ALERT > > # log_tcpdump: log packets in binary tcpdump format > # ------------------------------------------------- > # The only argument is the output file name. > # > # output log_tcpdump: tcpdump.log > > # database: log to a variety of databases > # --------------------------------------- > # See the README.database file for more information about configuring > # and using this plugin. > # > # output database: log, mysql, user=root password=test dbname=db > host=localhost > # output database: alert, postgresql, user=snort dbname=snort > # output database: log, unixodbc, user=snort dbname=snort > # output database: log, mssql, dbname=snort user=snort password=test > > # unified: Snort unified binary format alerting and logging > # ------------------------------------------------------------- > # The unified output plugin provides two new formats for logging > # and generating alerts from Snort, the "unified" format. The > # unified format is a straight binary format for logging data > # out of Snort that is designed to be fast and efficient. Used > # with barnyard (the new alert/log processor), most of the overhead > # for logging and alerting to various slow storage mechanisms > # such as databases or the network can now be avoided. > # > # Check out the spo_unified.h file for the data formats. > # > # Two arguments are supported. > # filename - base filename to write to (current time_t is appended) > # limit - maximum size of spool file in MB (default: 128) > # > # output alert_unified: filename snort.alert, limit 128 > # output log_unified: filename snort.log, limit 128 > > # You can optionally define new rule types and associate one or > # more output plugins specifically to that type. > # > # This example will create a type that will log to just tcpdump. > # ruletype suspicious > # { > # type log > # output log_tcpdump: suspicious.log > # } > # > # EXAMPLE RULE FOR SUSPICIOUS RULETYPE: > # suspicious $HOME_NET any -> $HOME_NET 6667 (msg:"Internal IRC Server";) > # > # This example will create a rule type that will log to syslog > # and a mysql database. > # ruletype redalert > # { > # type alert > # output alert_syslog: LOG_AUTH LOG_ALERT > # output database: log, mysql, user=snort dbname=snort host=localhost > # } > # > # EXAMPLE RULE FOR REDALERT RULETYPE > # redalert tcp $HOME_NET any -> $EXTERNAL_NET 31337 \ > # (msg:"Someone is being LEET"; flags:A+;) > > # > # Include classification & priority settings > # > > include classification.config > > # > # Include reference systems > # > > include reference.config > > ################################################## ################## > # Step #4: Customize your rule set > # > # Up to date snort rules are available at http://www.snort.org > # > # The snort web site has documentation about how to write your own > # custom snort rules. > # > # The rules included with this distribution generate alerts based on > # on suspicious activity. Depending on your network environment, your > # security policies, and what you consider to be suspicious, some of > # these rules may either generate false positives ore may be detecting > # activity you consider to be acceptable; therefore, you are > # encouraged to comment out rules that are not applicable in your > # environment. > # > # Note that using all of the rules at the same time may lead to > # serious packet loss on slower machines. YMMV, use with caution, > # standard disclaimers apply. :) > # > # The following individuals contributed many of rules in this > # distribution. > # > # Credits: > # Ron Gula <rgula@securitywizards.com> of Network Security Wizards > # Max Vision <vision@whitehats.com> > # Martin Markgraf <martin@mail.du.gtn.com> > # Fyodor Yarochkin <fygrave@tigerteam.net> > # Nick Rogness <nick@rapidnet.com> > # Jim Forster <jforster@rapidnet.com> > # Scott McIntyre <scott@whoi.edu> > # Tom Vandepoel <Tom.Vandepoel@ubizen.com> > # Brian Caswell <bmc@snort.org> > # Zeno <admin@cgisecurity.com> > # Ryan Russell <ryan@securityfocus.com> > # > #========================================= > # Include all relevant rulesets here > # > # shellcode, policy, info, backdoor, and virus rulesets are > # disabled by default. These require tuning and maintance. > # Please read the included specific file for more information. > #========================================= > > include $RULE_PATH/bad-traffic.rules > include $RULE_PATH/exploit.rules > include $RULE_PATH/scan.rules > include $RULE_PATH/finger.rules > include $RULE_PATH/ftp.rules > include $RULE_PATH/telnet.rules > include $RULE_PATH/rpc.rules > include $RULE_PATH/rservices.rules > include $RULE_PATH/dos.rules > include $RULE_PATH/ddos.rules > include $RULE_PATH/dns.rules > include $RULE_PATH/tftp.rules > > include $RULE_PATH/web-cgi.rules > include $RULE_PATH/web-coldfusion.rules > include $RULE_PATH/web-iis.rules > include $RULE_PATH/web-frontpage.rules > include $RULE_PATH/web-misc.rules > include $RULE_PATH/web-client.rules > include $RULE_PATH/web-php.rules > > include $RULE_PATH/sql.rules > include $RULE_PATH/x11.rules > include $RULE_PATH/icmp.rules > include $RULE_PATH/netbios.rules > include $RULE_PATH/misc.rules > include $RULE_PATH/attack-responses.rules > include $RULE_PATH/oracle.rules > include $RULE_PATH/mysql.rules > include $RULE_PATH/snmp.rules > > include $RULE_PATH/smtp.rules > include $RULE_PATH/imap.rules > include $RULE_PATH/pop2.rules > include $RULE_PATH/pop3.rules > > include $RULE_PATH/nntp.rules > include $RULE_PATH/other-ids.rules > # include $RULE_PATH/web-attacks.rules > # include $RULE_PATH/backdoor.rules > # include $RULE_PATH/shellcode.rules > # include $RULE_PATH/policy.rules > # include $RULE_PATH/porn.rules > # include $RULE_PATH/info.rules > # include $RULE_PATH/icmp-info.rules > # include $RULE_PATH/virus.rules > # include $RULE_PATH/chat.rules > # include $RULE_PATH/multimedia.rules > # include $RULE_PATH/p2p.rules > include $RULE_PATH/experimental.rules > include $RULE_PATH/local.rules > ----------------------------------------------------------------------------------- > >> >>pinging on your loopback will likely cause alerts because it's address is >>127.0.0.1, which is pretty unusual.. > > and ping execution result. > 1. to lo interface > PING 127.0.0.1 (127.0.0.1) from 127.0.0.1 : 56(84) bytes of data. > 64 bytes from 127.0.0.1: icmp_seq=0 ttl=255 time=48 usec > 64 bytes from 127.0.0.1: icmp_seq=1 ttl=255 time=32 usec > 64 bytes from 127.0.0.1: icmp_seq=2 ttl=255 time=39 usec > 64 bytes from 127.0.0.1: icmp_seq=3 ttl=255 time=31 usec > > 2.this machine eth interface (eth0) > PING 10.252.30.79 (10.252.30.79) from 10.252.30.79 : 56(84) bytes of data. > 64 bytes from 10.252.30.79: icmp_seq=0 ttl=255 time=47 usec > 64 bytes from 10.252.30.79: icmp_seq=1 ttl=255 time=34 usec > 64 bytes from 10.252.30.79: icmp_seq=2 ttl=255 time=37 usec > 64 bytes from 10.252.30.79: icmp_seq=3 ttl=255 time=40 usec > >> pinging a normal machine is pretty normal.. if you logged every such >>incident you'd have a pretty noisy sensor. > > actually, you whitten with in accord. > but not realize. why not execreason.??? > sorry. > want to give advices. > > Regards. > > ----------------- > Hideki Hirata > sphoenix@wtg.r-ts.co.jp > vega_1124_hdk@docomo.ne.jp > http://www7.freeweb.ne.jp/diary/sphoenix > > > ------------------------------------------------------- > This SF. Net email is sponsored by: GoToMyPC > GoToMyPC is the fast, easy and secure way to access your computer from > any Web browser or wireless device. Click here to Try it Free! > https://www.gotomypc.com/tr/OSDN/AW/...=mm/g22lp.tmpl > _______________________________________________ > Snort-users mailing list > Snort-users@lists.sourceforge.net > Go to this URL to change user options or unsubscribe: > https://lists.sourceforge.net/lists/...fo/snort-users > Snort-users list archive: > http://www.geocrawler.com/redir-sf.p...st=snort-users > Thanks, Josh Berry, CTO LinkNet-Solutions 469-831-8543 josh.berry@linknet-solutions.com ------------------------------------------------------- This SF. Net email is sponsored by: GoToMyPC GoToMyPC is the fast, easy and secure way to access your computer from any Web browser or wireless device. Click here to Try it Free! https://www.gotomypc.com/tr/OSDN/AW/...=mm/g22lp.tmpl _______________________________________________ Snort-users mailing list Snort-users@lists.sourceforge.net Go to this URL to change user options or unsubscribe: https://lists.sourceforge.net/lists/...fo/snort-users Snort-users list archive: http://www.geocrawler.com/redir-sf.p...st=snort-users |
![]() |
| Thread Tools | |
| Display Modes | |
|
|