Fortinet Comprehensive Guide to Fortigate IPS Sensors, Profiles, and Signature Lists

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IPS sensors	Viewing the IPS sensor list

IPS sensors

You can group signatures into IPS sensors for easy selection in protection profiles. You can define signatures for specific types of traffic in separate IPS sensors, and then select those sensors in profiles designed to handle that type of traffic. For example, you can specify all of the web-server related signatures in an IPS sensor, and the sensor can then be used by a protection profile in a policy that controls all of the traffic to and from a web server protected by the FortiGate unit.

The FortiGuard Service periodically updates the pre-defined signatures, with signatures added to counter new threats. Because the signatures included in filters are defined by specifying signature attributes, new signatures matching existing filter specifications will automatically be included in those filters. For example, if you have a filter that includes all signatures for the Windows operating system, your filter will automatically incorporate new Windows signatures as they are added.

This section describes:

•Viewing the IPS sensor list

•Configuring IPS sensors

Viewing the IPS sensor list

To view the IPS sensors, go to Intrusion Protection > IPS Sensor.

Figure 7: IPS Sensor list showing the default sensors

The IPS sensor list displays the following information.

Create New	Add a new IPS sensor. For more information, see “Adding an
	IPS sensor” on page 40.
Name	The name of each IPS sensor.
Comments	An optional description of the IPS sensor.
Delete and Edit icons	Delete or edit an IPS sensor.

Five default IPS sensors are provided with the default configuration.

all_default	Includes all signatures. The sensor is set to use the default
	enable status and action of each signature.
all_default_pass	Includes all signatures. The sensor is set to use the default
	enable status of each signature, but the action is set to pass.

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Contents E R G U I D E Trademarks Contents SYN flood attacks Protocol decodersIPS sensors DoS sensorsFortiGate IPS IntroductionTypographic conventions About this documentFortinet documentation Document conventionsFortiGate Pptp VPN User Guide Customer service and technical support Fortinet Knowledge CenterComments on Fortinet technical documentation IPS overview and general configuration IPS settings and controlsThis section contains the following topics Config ips global Set fail-open enable disable end When to use IPSDefault signature and anomaly settings Default fail open settingControlling sessions Setting the buffer sizeConfiguring logging and alert email Monitoring the network and dealing with attacksAttack log messages Signature FortiGuard Center AnomalySelect Create New Using IPS sensors in a protection profileCreating a protection profile that uses IPS sensors Adding protection profiles to firewall policiesAdding protection profiles to user groups Using IPS sensors in a protection profile Predefined signatures IPS predefined signaturesViewing the predefined signature list Clear All Filters SettingsEnable ColumnCreate a sensor and add IPS filters to it Viewing the predefined signature list Custom signatures IPS custom signaturesViewing the custom signature list Command syntax pattern Custom signature configurationAdding custom signatures using the web-based manager Adding custom signatures using the CLICreating custom signatures Custom signature fieldsShows the valid characters for custom signature fields Srcport Custom signature syntaxAttackid Name BufferOverflowContent keywords Keyword and value Description Deprecated, see pattern and context keywords Context host Pattern GETContext uri Pattern yahoo.comUri !uristr PcreRegex/mdelim RegexdelimismxAEGRUIP header keywords Keyword and Value Description Protocol tcpTCP header keywords Keyword and Value Description Tcpflags S,12 Tcpflags APUDP header keywords Keyword and Value Description Icmp keywords Keyword and Value UsageOther keywords Keyword and Value Description Example 1 signature to block access to example.com Example custom signaturesSbid --name Block.example.com Sbid --name Block.example.com Example 2 signature to block the Smtp ‘vrfy’ command Sbid --name Block.SMTP.VRFY.CMDSbid --name Block.SMTP.VRFY.CMD --pattern vrfy Creating custom signatures Protocol decoders Protocol decodersUpgrading the IPS protocol decoder list Protocol decoder list Protocols Protocol decoder names Port Viewing the protocol decoder listViewing the IPS sensor list AlldefaultAlldefaultpass IPS sensorsProtectemailserver Configuring IPS sensorsAdding an IPS sensor ProtectclientIPS sensor filters IPS sensor attributesDelete and Edit Delete or edit the filter Icons Configuring filtersReset IPS sensor overridesApplication Configuring pre-defined and custom overridesSource Exempt IPDoS sensors Appears, and select OK Configuring DoS sensorsViewing the DoS sensor list Sequence in which the sensors examine network trafficWill appear in the DoS sensor list Anomaly configurationDoS sensor attributes Name Enter or change the DoS sensor name CommentsUnderstanding the anomalies Udpsrcsession Anomaly Description TcpdstsessionUdpflood UdpscanUnderstanding the anomalies What is a SYN flood attack? SYN flood attacksHow SYN floods work How IPS works to prevent SYN floods What is SYN threshold?What is SYN proxy? FortiGate IPS Response to SYN flood attacksIPS operation before synflood threshold is reached Configuring SYN flood protection Suggested settings for different network conditionsConfigure the options for tcpsynflood Select OK FortiGate IPS response to Icmp sweep attacks What is an Icmp sweep?Icmp sweep attacks How Icmp sweep attacks workPredefined Icmp signatures Icmp sweep anomalies Configuring Icmp sweep protection FortiGate Version 3.0 MR7 IPS User Guide IndexTechnical support