Contents | Fortinet IPS specs

Contents

Contents
Introduction	5
The FortiGate IPS	5
About this document	6
Document conventions	6
Fortinet documentation	6
Fortinet Knowledge Center	8
Comments on Fortinet technical documentation	8
Customer service and technical support	8
IPS overview and general configuration	9
The FortiGate IPS	9
IPS settings and controls	9
When to use IPS	10
Network performance	10
Default signature and anomaly settings	10
Default fail open setting	10
Controlling sessions	11
Setting the buffer size	11
Monitoring the network and dealing with attacks	11
Configuring logging and alert email	11
Attack log messages	12
The FortiGuard Center	13
Using IPS sensors in a protection profile	14
Creating a protection profile that uses IPS sensors	14
Adding protection profiles to firewall policies	14
Adding protection profiles to user groups	15
Predefined signatures	17
IPS predefined signatures	17
Viewing the predefined signature list	17
Fine tuning IPS predefined signatures for enhanced system performance	18
Custom signatures	21
IPS custom signatures	21
Viewing the custom signature list	21
Custom signature configuration	22
Adding custom signatures using the web-based manager	22
Adding custom signatures using the CLI	22

FortiGate IPS User Guide Version 3.0 MR7
01-30007-0080-20080916	3

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Fortinet IPS manual Contents

Contents

E R G U I D E Trademarks Contents SYN flood attacks Protocol decodersIPS sensors DoS sensors FortiGate IPS Introduction Typographic conventions About this documentFortinet documentation Document conventions FortiGate 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 setting Controlling sessions Setting the buffer sizeConfiguring logging and alert email Monitoring the network and dealing with attacks Attack log messages Signature FortiGuard Center Anomaly Select Create New Using IPS sensors in a protection profileCreating a protection profile that uses IPS sensors Adding protection profiles to firewall policies Adding 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 Column Create 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 CLI Creating custom signatures Custom signature fieldsShows the valid characters for custom signature fields Srcport Custom signature syntaxAttackid Name BufferOverflow Content keywords Keyword and value Description Deprecated, see pattern and context keywords Context host Pattern GETContext uri Pattern yahoo.com Uri !uristr PcreRegex/mdelim RegexdelimismxAEGRU IP header keywords Keyword and Value Description Protocol tcp TCP header keywords Keyword and Value Description Tcpflags S,12 Tcpflags AP UDP 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 list Viewing the IPS sensor list AlldefaultAlldefaultpass IPS sensors Protectemailserver Configuring IPS sensorsAdding an IPS sensor Protectclient IPS sensor filters IPS sensor attributes Delete and Edit Delete or edit the filter Icons Configuring filtersReset IPS sensor overrides Application Configuring pre-defined and custom overrides Source Exempt IP DoS sensors Appears, and select OK Configuring DoS sensorsViewing the DoS sensor list Sequence in which the sensors examine network traffic Will appear in the DoS sensor list Anomaly configurationDoS sensor attributes Name Enter or change the DoS sensor name Comments Understanding the anomalies Udpsrcsession Anomaly Description TcpdstsessionUdpflood Udpscan Understanding 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 attacks IPS 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 work Predefined Icmp signatures Icmp sweep anomalies Configuring Icmp sweep protection FortiGate Version 3.0 MR7 IPS User Guide Index Technical support