Collect Zscaler Firewall logs

Supported in:

Google secops SIEM

This document describes how you can export Zscaler Firewall logs by setting up a Google Security Operations feed and how log fields map to Google SecOps Unified Data Model (UDM) fields.

For more information, see Data ingestion to Google SecOps overview.

A typical deployment consists of Zscaler Firewall and the Google SecOps Webhook feed configured to send logs to Google SecOps. Each customer deployment can differ and might be more complex.

The deployment contains the following components:

Zscaler Firewall: The platform from which you collect logs.
Google SecOps feed: The Google SecOps feed that fetches logs from Zscaler Firewall and writes logs to Google SecOps.
Google SecOps: Retains and analyzes the logs.

An ingestion label identifies the parser which normalizes raw log data to structured UDM format. The information in this document applies to the parser with the ZSCALER_FIREWALL ingestion label.

Before you begin

Ensure you have the following prerequisites:

Access to Zscaler Internet Access console. For more information, see Secure Internet and SaaS Access ZIA Help.
Zscaler Firewall 2024 or later
All systems in the deployment architecture are configured with the UTC time zone.
The API key which is needed to complete feed setup in Google Security Operations. For more information, see Setting up API keys.

Set up feeds

To configure this log type, follow these steps:

Go to SIEM Settings > Feeds.
Click Add New Feed.
Click the Zscaler feed pack.
Locate the required log type and click Add New Feed.
Enter values for the following input parameters:
- Source Type: Webhook (Recommended)
- Split delimiter: the character used to separate logs lines. Leave blank if no delimiter is used.
Advanced options
- Feed Name: A prepopulated value that identifies the feed.
- Asset Namespace: Namespace associated with the feed.
- Ingestion Labels: Labels applied to all events from this feed.
Click Create Feed.

For more information about configuring multiple feeds for different log types within this product family, see Configure feeds by product.

Set up Zscaler Firewall

In the Zscaler Internet Access console, click Administration > Nanolog Streaming Service > Cloud NSS Feeds and then click Add Cloud NSS Feed.
The Add Cloud NSS Feed window appears. In the Add Cloud NSS Feed window, enter the details.
Enter a name for the feed in the Feed Name field.
Select NSS for Firewall in NSS Type.
Select the status from the Status list to activate or deactivate the NSS feed.
Keep the value in the SIEM Rate drop-down as Unlimited. To suppress the output stream due to licensing or other constraints, change the value.
Select Other in the SIEM Type list.
Select Disabled in the OAuth 2.0 Authentication list.
Enter a size limit for an individual HTTP request payload to the SIEM's best practice in Max Batch Size. For example, 512 KB.
Enter the HTTPS URL of the Chronicle API endpoint in the API URL in the following format:
```
  https://<CHRONICLE_REGION>-chronicle.googleapis.com/v1alpha/projects/<GOOGLE_PROJECT_NUMBER>/locations/<LOCATION>/instances/<CUSTOMER_ID>/feeds/<FEED_ID>:importPushLogs
```
- CHRONICLE_REGION: Region where your Chronicle instance is hosted. For example, US.
- GOOGLE_PROJECT_NUMBER: BYOP project number. Obtain this from C4.
- LOCATION: Chronicle region. For example, US.
- CUSTOMER_ID: Chronicle customer ID. Obtain from C4.
- FEED_ID: Feed ID shown on Feed UI on the new webhook created
- Sample API URL:
```
https://us-chronicle.googleapis.com/v1alpha/projects/12345678910/locations/US/instances/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx/feeds/yyyyyyyy-yyyy-yyyy-yyyy-yyyyyyyyyyyy:importPushLogs
```
Click Add HTTP Header, and then add HTTP headers in the following format:
- Header 1: Key1: X-goog-api-key and Value1: API Key generated on Google Cloud BYOP's API Credentials.
- Header 2: Key2: X-Webhook-Access-Key and Value2: API secret key generated on webhook's "SECRET KEY".
Select Firewall Logs in the Log Types list.
Select JSON in the Feed Output Type list.
Set Feed Escape Character to , \ ".
To add a new field to the Feed Output Format, select Custom in the Feed Output Type list.
Copy-paste the Feed Output Format and add new fields. Ensure the key names match the actual field names.

Following is the default Feed Output Format:

  \{ "sourcetype" : "zscalernss-fw", "event" :\{"datetime":"%s{time}","user":"%s{elogin}","department":"%s{edepartment}","locationname":"%s{elocation}","cdport":"%d{cdport}","csport":"%d{csport}","sdport":"%d{sdport}","ssport":"%d{ssport}","csip":"%s{csip}","cdip":"%s{cdip}","ssip":"%s{ssip}","sdip":"%s{sdip}","tsip":"%s{tsip}","tunsport":"%d{tsport}","tuntype":"%s{ttype}","action":"%s{action}","dnat":"%s{dnat}","stateful":"%s{stateful}","aggregate":"%s{aggregate}","nwsvc":"%s{nwsvc}","nwapp":"%s{nwapp}","proto":"%s{ipproto}","ipcat":"%s{ipcat}","destcountry":"%s{destcountry}","avgduration":"%d{avgduration}","rulelabel":"%s{erulelabel}","inbytes":"%ld{inbytes}","outbytes":"%ld{outbytes}","duration":"%d{duration}","durationms":"%d{durationms}","numsessions":"%d{numsessions}","ipsrulelabel":"%s{ipsrulelabel}","threatcat":"%s{threatcat}","threatname":"%s{ethreatname}","deviceowner":"%s{deviceowner}","devicehostname":"%s{devicehostname}"\}\}

Select the timezone for the Time field in the output file in the Timezone list. By default, the timezone is set to your organization's time zone.
Review the configured settings.
Click Save to test connectivity. If the connection is successful, a green tick accompanied by the message Test Connectivity Successful: OK (200) appears.

For more information about Google SecOps feeds, see Google SecOps feeds documentation. For information about requirements for each feed type, see Feed configuration by type.

If you encounter issues when you create feeds, contact Google SecOps support.

Supported Zscaler Firewall log formats

The Zscaler Firewall parser supports logs in JSON format.

Supported Zscaler Firewall Sample Logs

JSON:

{
  "sourcetype": "zscalernss-fw",
  "event": {
    "datetime": "Tue Apr 11 00:44:01 2023",
    "user": "abc@test.com",
    "department": "Optum%20Tech%20UHC%20Technology",
    "locationname": "Road%20Warrior",
    "cdport": "443",
    "csport": "50407",
    "sdport": "443",
    "ssport": "36223",
    "csip": "198.51.100.8",
    "cdip": "198.51.100.7",
    "ssip": "198.51.100.9",
    "sdip": "198.51.100.10",
    "tsip": "198.51.100.11",
    "tunsport": "0",
    "tuntype": "ZscalerClientConnector",
    "action": "Allow",
    "dnat": "No",
    "stateful": "Yes",
    "aggregate": "Yes",
    "nwsvc": "ZSCALER_PROXY_NW_SERVICES",
    "nwapp": "sharepoint_document",
    "proto": "TCP",
    "ipcat": "Miscellaneous or Unknown",
    "destcountry": "Other",
    "avgduration": "239296",
    "rulelabel": "Default%20Firewall%20Filtering%20Rule",
    "inbytes": "286134",
    "outbytes": "515005",
    "duration": "6461",
    "durationms": "6461000",
    "numsessions": "27",
    "ipsrulelabel": "None",
    "threatcat": "None",
    "threatname": "None",
    "deviceowner": "dummydeviceowner",
    "devicehostname": "dummyhostname"
  }
}

Field mapping reference

The following table lists the log fields of the ZSCALER_FIREWALL log type and their corresponding UDM fields.

Log field	UDM mapping	Logic
`fwd_gw_name`	`intermediary.resource.name`
	`intermediary.resource.resource_type`	If the `fwd_gw_name` log field value is not empty or the `ofwd_gw_name` log field value is not empty, then the `intermediary.resource.resource_type` UDM field is set to `GATEWAY`.
`ofwd_gw_name`	`intermediary.security_result.detection_fields[ofwd_gw_name]`
`ordr_rulename`	`intermediary.security_result.detection_fields[ordr_rulename]`
`orulelabel`	`intermediary.security_result.detection_fields[orulelabel]`
`rdr_rulename`	`intermediary.security_result.rule_name`
`rulelabel`	`intermediary.security_result.rule_name`
`erulelabel`	`intermediary.security_result.rule_name`
`bypass_etime`	`metadata.collected_timestamp`
`datetime`	`metadata.event_timestamp`
`epochtime`	`metadata.event_timestamp`
	`metadata.event_type`	If the `sdport` log field value is equal to `80` or the `sdport` log field value is equal to `443` and the `csip` log field value is not empty or the `tsip` log field value is not empty or the `ssip` log field value is not empty and the `cdip` log field value is not empty or the `sdip` log field value is not empty, then the `metadata.event_type` UDM field is set to `NETWORK_HTTP`. Else, if the `csip` log field value is not empty or the `tsip` log field value is not empty or the `ssip` log field value is not empty and the `cdip` log field value is not empty or the `sdip` log field value is not empty, then the `metadata.event_type` UDM field is set to `NETWORK_CONNECTION`. Else, if the `csip` log field value is not empty or the `tsip` log field value is not empty or the `ssip` log field value is not empty, then the `metadata.event_type` UDM field is set to `STATUS_UPDATE`. Else, the `metadata.event_type` UDM field is set to `GENERIC_EVENT`.
`recordid`	`metadata.product_log_id`
	`metadata.product_name`	The `metadata.product_name` UDM field is set to `Firewall`.
	`metadata.vendor_name`	The `metadata.vendor_name` UDM field is set to `Zscaler`.
`proto`	`network.ip_protocol`	If the `proto` log field value contain one of the following values, then the `proto` log field is mapped to the `network.ip_protocol` UDM field. `TCP` `UDP` `ICMP` `GRE` `IP6IN4` `IGMP`
`inbytes`	`network.received_bytes`
`outbytes`	`network.sent_bytes`
`avgduration`	`network.session_duration.nanos`	If the `durationms` log field value is empty and the `avgduration` log field value is not empty, then the `avgduration` log field is mapped to the `network.session_duration.nanos` UDM field.
`durationms`	`network.session_duration.nanos`	If the `durationms` log field value is not empty, then the `durationms` log field is mapped to the `network.session_duration.nanos` UDM field.
`duration`	`network.session_duration.seconds`
`devicename`	`principal.asset.asset_id`	If the `devicename` log field value is not empty, then the `Zscaler:devicename` log field is mapped to the `principal.asset.asset_id` UDM field.
`devicemodel`	`principal.asset.hardware.model`
`devicehostname`	`principal.asset.hostname`	If the `devicehostname` log field value is not empty, then the `devicehostname` log field is mapped to the `principal.asset.hostname` UDM field.
	`principal.asset.platform_software.platform`	If the `deviceostype` log field value matches the regular expression pattern `(?i)iOS`, then the `principal.asset.platform_software.platform` UDM field is set to `IOS`. Else, if the `deviceostype` log field value matches the regular expression pattern `(?i)Android`, then the `principal.asset.platform_software.platform` UDM field is set to `ANDROID`. Else, if the `deviceostype` log field value matches the regular expression pattern `(?i)Windows`, then the `principal.asset.platform_software.platform` UDM field is set to `WINDOWS`. Else, if the `deviceostype` log field value matches the regular expression pattern `(?i)MAC`, then the `principal.asset.platform_software.platform` UDM field is set to `MAC`. Else, if the `deviceostype` log field value matches the regular expression pattern `(?i)Other`, then the `principal.asset.platform_software.platform` UDM field is set to `UNKNOWN_PLATFORM`.
`deviceosversion`	`principal.asset.platform_software.platform_version`
`external_deviceid`	`principal.asset.product_object_id`
`csip`	`principal.ip`
`tsip`	`principal.ip`
`srcip_country`	`principal.location.country_or_region`
`location`	`principal.location.name`
`locationname`	`principal.location.name`
`ssip`	`principal.nat_ip`
`ssport`	`principal.nat_port`
`csport`	`principal.port`
`dept`	`principal.user.department`
`department`	`principal.user.department`
`login`	`principal.user.email_addresses`	The `login` field is extracted from `login` log field using the Grok pattern, and the `login` log field is mapped to the `principal.user.email_addresses` UDM field.
`user`	`principal.user.email_addresses`	The `user` field is extracted from `user` log field using the Grok pattern, and the `user` log field is mapped to the `principal.user.email_addresses` UDM field.
`deviceowner`	`principal.user.userid`
	`security_result.action`	If the `action` log field value matches the regular expression pattern `^Allow.`, then the `security_result.action` UDM field is set to `ALLOW`. Else, if the `action` log field value matches the regular expression pattern `^Drop.` or `^Block.*`, then the `security_result.action` UDM field is set to `BLOCK`. Else, if the `action` log field value is equal to `Reset`, then the `security_result.action` UDM field is set to `BLOCK`.
`action`	`security_result.action_details`
`threat_severity,threat_score`	`security_result.severity`	If the `threat_severity` log field value is one of the following: `CRITICAL`, `HIGH`, `MEDIUM`, `LOW`, `NONE` then, the `threat_severity` log field is mapped to the `security_result.severity` UDM field. Else, if the `threat_score` log field value is equal to `0` then, the `security_result.severity` UDM field is set to `NONE`. Else, if `threat_score` log field value > `0` and the `threat_score` log field value <= `45` then, the `security_result.severity` UDM field is set to `LOW`. Else, if `threat_score` log field value > `45` and the `threat_score` log field value < `75` then, the `security_result.severity` UDM field is set to `MEDIUM`. Else, if `threat_score` log field value >= `75` and the `threat_score` log field value < `90` then, the `security_result.severity` UDM field is set to `HIGH`. Else, if `threat_score` log field value >= `90` and the `threat_score` log field value <= `100` then, the `security_result.severity` UDM field is set to `CRITICAL`.
`threat_severity,threat_score`	`security_result.severity_details`	If the `threat_score` log field value is not empty and the `threat_severity` log field value is not empty then, `%{threat_score} - %{threat_severity}` log field is mapped to the `security_result.severity_details` UDM field. Else, if `threat_severity` log field value is not empty then, `threat_severity` log field is mapped to the `security_result.severity_details` UDM field. Else, if `threat_score` log field value is not empty then, `threat_score` log field is mapped to the `security_result.severity_details` UDM field.
	`security_result.category`	If the `ipcat` log field value is not empty or the `oipcat` log field value is not empty, then the `security_result.category` UDM field is set to `NETWORK_CATEGORIZED_CONTENT`.
`ipcat`	`security_result.category_details`	The `ipcat` log field is mapped to the `security_result.category_details` UDM field.
`threatcat`	`security_result.category_details`	If the `threatcat` log field value is not equal to `None`, then the `threatcat` log field is mapped to the `security_result.category_details` UDM field.
	`security_result.detection_fields[bypassed_session]`	If the `bypassed_session` log field value is equal to `0`, then the `security_result.detection_fields.bypassed_session` UDM field is set to `the traffic did not bypass Zscaler Client Connector`. Else, if the `bypassed_session` log field value is equal to `1`, then the `security_result.detection_fields.bypassed_session` UDM field is set to `the traffic bypassed Zscaler Client Connector`.
`odevicehostname`	`security_result.detection_fields[odevicehostname]`
`odevicename`	`security_result.detection_fields[odevicename]`
`odeviceowner`	`security_result.detection_fields[odeviceowner]`
`oipcat`	`security_result.detection_fields[oipcat]`
`oipsrulelabel`	`security_result.detection_fields[oipsrulelabel]`
`numsessions`	`security_result.detection_fields[numsessions]`
	`security_result.rule_labels [ips_custom_signature]`	If the `ips_custom_signature` log field value is equal to `0`, then the `security_result.rule_labels.ips_custom_signature` UDM field is set to `non-custom IPS rule`. Else, if the `ips_custom_signature` log field value is equal to `1`, then the `security_result.rule_labels.ips_custom_signature` UDM field is set to `custom IPS rule`.
`ipsrulelabel`	`security_result.rule_name`	If the `ipsrulelabel` log field value is not equal to `None`, then the `ipsrulelabel` log field is mapped to the `security_result.rule_name` UDM field.
`threatname`	`security_result.threat_name`	If the `threatname` log field value is not equal to `None`, then the `threatname` log field is mapped to the `security_result.threat_name` UDM field.
`ethreatname`	`security_result.threat_name`	If the `ethreatname` log field value is not equal to `None`, then the `ethreatname` log field is mapped to the `security_result.threat_name` UDM field.
`nwapp`	`target.application`
`cdfqdn`	`target.domain.name`
`sdip`	`target.ip`
`datacentercity`	`target.location.city`
`destcountry`	`target.location.country_or_region`
`datacentercountry`	`target.location.country_or_region`
`datacenter`	`target.location.name`
`cdip`	`target.nat_ip`
`cdport`	`target.nat_port`
`sdport`	`target.port`
`odnatlabel`	`target.security_result.detection_fields[odnatlabel]`
`dnat`	`target.security_result.rule_labels[dnat]`
`dnatrulelabel`	`target.security_result.rule_name`
`aggregate`	`additional.fields[aggregate]`
`day`	`additional.fields[day]`
`dd`	`additional.fields[dd]`
`deviceappversion`	`additional.fields[deviceappversion]`
`eedone`	`additional.fields[eedone]`
`flow_type`	`additional.fields[flow_type]`
`hh`	`additional.fields[hh]`
`mm`	`additional.fields[mm]`
`mon`	`additional.fields[mon]`
`mth`	`additional.fields[mth]`
`nwsvc`	`additional.fields[nwsvc]`
`ocsip`	`additional.fields[ocsip]`
`ozpa_app_seg_name`	`additional.fields[ozpa_app_seg_name]`
`ss`	`additional.fields[ss]`
`sourcetype`	`additional.fields[sourcetype]`
`stateful`	`additional.fields[stateful]`
`tz`	`additional.fields[tz]`
`tuntype`	`additional.fields[traffic_forwarding_method]`
`tunsport`	`additional.fields[tunsport]`
`yyyy`	`additional.fields[yyyy]`
`zpa_app_seg_name`	`additional.fields[zpa_app_seg_name]`
`ztunnelversion`	`additional.fields[ztunnelversion]`

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