Cloudflare DNS Gateway
Overview
Cloudflare is a global network designed to make everything you connect to the Internet secure, private, fast, and reliable. In this documentation, you will learn how to collect and send Cloudflare Gateway DNS logs to Sekoia.io.
- Vendor: Cloudflare
- Plan: Defend Prime
- Supported environment: SaaS
- Detection based on: Telemetry
- Supported application or feature: DNS records
Configuration
Create the intake on Sekoia.io
Go to the intake page and create a new intake from the format Cloudflare.
Configure events forwarding on Cloudflare
Retrieve necessary information
First, you will have to retrieve configuration information. Connect to Cloudflare Console to collect the following :
-
Cloudflare API Token
- Go to
My Profile, then on the left panel, click onAPI Tokens. - Click on the
Create Tokenbutton and select theCreate Custom Tokenentry. - Give a name to your token and set the following permissions:
Scope Group Level Account Account Analytics Read Account Logs Read Account Logs Edit Zone Logs Read Zone Logs Edit - If you want zerotrust logs you should also add:
Scope Group Level Account Zero Trust Read - Go to
-
Cloudflare Zone ID :
- This information is specific to a Website.
- On the left panel, click on
Websitesand select the Website you want. - On the right panel, there is an
APIsection where you can retrieve theZone ID.
Create a Logpush job
Configure a Logpush job with the following destination:
https://intake.sekoia.io/plain/batch?header_X-SEKOIAIO-INTAKE-KEY=<YOUR_INTAKE_KEY>
To do so, you can manage Logpush with cURL:
$ curl -X POST 'https://api.cloudflare.com/client/v4/accounts/<CLOUDFLARE_ACCOUNT_ID>/logpush/jobs' \
-H 'Authorization: Bearer <CLOUDFLARE_API_TOKEN>' \
-H "Content-Type: application/json" \
-d '{
"dataset": "gateway_dns",
"enabled": true,
"max_upload_bytes": 5000000,
"max_upload_records": 1000,
"logpull_options":"fields=ApplicationID,ColoCode,ColoID,Datetime,DeviceID,DeviceName,DstIP,DstPort,Email,Location,LocationID,MatchedCategoryIDs,MatchedCategoryNames,Policy,PolicyID,Protocol,QueryCategoryIDs,QueryCategoryNames,QueryName,QueryNameReversed,QuerySize,QueryType,QueryTypeName,RCode,RData,ResolvedIPs,ResolverDecision,SrcIP,SrcPort,TimeZone,TimeZoneInferredMethod,UserID×tamps=rfc3339",
"destination_conf": "https://intake.sekoia.io/plain/batch?header_X-SEKOIAIO-INTAKE-KEY=<YOUR_INTAKE_KEY>"
}' # (1)
- will return
{ "errors": [], "messages": [], "result": { "id": "<ID>", "dataset": "gateway_dns", "frequency":"high", "kind":"", "max_upload_bytes": 5000000, "max_upload_records": 1000, "enabled": true, "name": "<DOMAIN_NAME>", "logpull_options": "fields=<LIST_OF_FIELDS>", "destination_conf": "https://intake.sekoia.io/plain/batch?header_X-SEKOIAIO-INTAKE-KEY=<YOUR_INTAKE_KEY>", "last_complete": null, "last_error": null, "error_message": null, "time_created":"<TIMESTAMP>" }, "success": true }
Important
Replace :
<YOUR_INTAKE_KEY>with the Intake key you generated in the Create the intake on Sekoia.io step.<CLOUDFLARE_ACCOUNT_ID>with the ACCOUNT_ID found on the overview page<CLOUDFLARE_API_TOKEN>with the API Token you generated
Useful Cloudflare API endpoints
On their documentation, Cloudflare provides a list API endpoints you can use. Find below some useful endpoints:
https://api.cloudflare.com/client/v4/accounts/<ACCOUNT_ID>/logpush/jobs/<JOB_ID>to verify the job you previously created is correct (you need to specify theJOB_ID)https://api.cloudflare.com/client/v4/accounts/<ACCOUNT_ID>/logpush/datasets/<DATASET>/jobsto get all the jobs for a specific dataset (dns_log,firewalls_eventsorhttp_requestsin our case)https://api.cloudflare.com/client/v4/accounts/<ACCOUNT_ID>/logpush/jobs/<JOB_ID>to update a job if you noticed a mistake after the creation of the job (wrong fields, wrong SEKOIA API Key...)
Raw Events Samples
In this section, you will find examples of raw logs as generated natively by the source. These examples are provided to help integrators understand the data format before ingestion into Sekoia.io. It is crucial for setting up the correct parsing stages and ensuring that all relevant information is captured.
{
"ApplicationID": 0,
"ColoCode": "CDG",
"ColoID": 533,
"Datetime": "2023-02-24T12:12:07Z",
"DeviceID": "",
"DeviceName": "",
"DstIP": "172.12.12.1",
"DstPort": 23,
"Email": "",
"Location": "AWS VM",
"LocationID": "a26c188f-10c2-4333-8ed4-c823fafa06f6",
"MatchedCategoryIDs": [],
"MatchedCategoryNames": [],
"Policy": "",
"PolicyID": "",
"Protocol": "udp",
"QueryCategoryIDs": [],
"QueryCategoryNames": [],
"QueryName": "ip-111-30-40-252.eu-west-3.compute.internal",
"QueryNameReversed": "internal.compute.eu-west-3.ip-111-30-40-252",
"QuerySize": 72,
"QueryType": 1,
"QueryTypeName": "A",
"RCode": 3,
"RData": [],
"ResolvedIPs": [
"104.18.4.35",
"104.18.5.35"
],
"ResolverDecision": "allowedOnNoPolicyMatch",
"SrcIP": "12.122.186.81",
"SrcPort": 42424,
"TimeZone": "",
"TimeZoneInferredMethod": "noScheduleConfigured",
"UserID": ""
}
{
"ApplicationID": 0,
"ColoCode": "CDG",
"ColoID": 534,
"Datetime": "2023-05-02T16:24:19Z",
"DeviceID": "b72ac397-e5c3-913e-11ed-03face9f2b6b",
"DeviceName": "DESKTOP-ABCDEF",
"DstIP": "162.159.36.1",
"DstPort": 443,
"Email": "john.doe@test.com",
"Location": "loc-01",
"LocationID": "a26c158f-10c2-4223-8ed4-c845fafa06f6",
"MatchedCategoryIDs": [],
"MatchedCategoryNames": [],
"Policy": "",
"PolicyID": "",
"Protocol": "https",
"QueryCategoryIDs": [
21,
80
],
"QueryCategoryNames": [
"Security threats",
"Command and Control & Botnet"
],
"QueryName": "commandandcontrolandbotnet.testcategory.com",
"QueryNameReversed": "com.testcategory.commandandcontrolandbotnet",
"QuerySize": 72,
"QueryType": 65,
"QueryTypeName": "HTTPS",
"RCode": 0,
"RData": [
{
"type": "65",
"data": "GmNvbW1hbmRhbmRjb250cm9sYW5kYm90bmV0DHRlc3RjYXRlZ29yeQNjb20AAEEAAQAAADwAOgABAAABAAMCaDIABAAIaBIEI2gSBSMABgAgJgZHAAAAAAAAAAAAaBIEIyYGRwAAAAAAAAAAAGgSBSM="
}
],
"ResolvedIPs": [],
"ResolverDecision": "allowedOnNoPolicyMatch",
"SrcIP": "15.188.186.81",
"SrcPort": 0,
"TimeZone": "",
"TimeZoneInferredMethod": "noScheduleConfigured",
"UserID": "2c46cdd9-92e3-5e5f-b3cf-67965d7c33e3"
}
Detection section
The following section provides information for those who wish to learn more about the detection capabilities enabled by collecting this intake. It includes details about the built-in rule catalog, event categories, and ECS fields extracted from raw events. This is essential for users aiming to create custom detection rules, perform hunting activities, or pivot in the events page.
Related Built-in Rules
The following Sekoia.io built-in rules match the intake Cloudflare Gateway DNS. This documentation is updated automatically and is based solely on the fields used by the intake which are checked against our rules. This means that some rules will be listed but might not be relevant with the intake.
SEKOIA.IO x Cloudflare Gateway DNS on ATT&CK Navigator
Bazar Loader DGA (Domain Generation Algorithm)
Detects Bazar Loader domains based on the Bazar Loader DGA
- Effort: elementary
Cobalt Strike DNS Beaconing
Detects suspicious DNS queries known from Cobalt Strike beacons. The threshold is more than 50 suspicious DNS requests to avoid false positives.
- Effort: advanced
Correlation Potential DNS Tunnel
Detects domain name which is longer than 95 characters. Long domain names are distinctive of DNS tunnels.
- Effort: advanced
Cryptomining
Detection of domain names potentially related to cryptomining activities.
- Effort: master
Dynamic DNS Contacted
Detect communication with dynamic dns domain. This kind of domain is often used by attackers. This rule can trigger false positive in non-controlled environment because dynamic dns is not always malicious.
- Effort: master
EvilProxy Phishing Domain
Detects subdomains potentially generated by the EvilProxy adversary-in-the-middle phishing platform. Inspect the other subdomains of the domain to identify the landing page, and determine if the user submitted credentials. This rule has a small percentage of false positives on legitimate domains.
- Effort: intermediate
Exfiltration Domain
Detects traffic toward a domain flagged as a possible exfiltration vector.
- Effort: master
Potential DNS Tunnel
Detects domain name which is longer than 95 characters. Long domain names are distinctive of DNS tunnels.
- Effort: advanced
Remote Access Tool Domain
Detects traffic toward a domain flagged as a Remote Administration Tool (RAT).
- Effort: master
Remote Monitoring and Management Software - AnyDesk
Detect artifacts related to the installation or execution of the Remote Monitoring and Management tool AnyDesk.
- Effort: master
Remote Monitoring and Management Software - Atera
Detect artifacts related to the installation or execution of the Remote Monitoring and Management tool Atera.
- Effort: master
SEKOIA.IO Intelligence Feed
Detect threats based on indicators of compromise (IOCs) collected by SEKOIA's Threat and Detection Research team.
- Effort: elementary
Sekoia.io EICAR Detection
Detects observables in Sekoia.io CTI tagged as EICAR, which are fake samples meant to test detection.
- Effort: master
Sliver DNS Beaconing
Detects suspicious DNS queries known from Sliver beaconing
- Effort: intermediate
Suspicious TOR Gateway
Detects suspicious TOR gateways. Gateways are often used by the victim to pay and decrypt the encrypted files without installing TOR. Tor intercepts the network traffic from one or more apps on user’s computer, usually the user web browser, and shuffles it through a number of randomly-chosen computers before passing it on to its destination. This disguises user location, and makes it harder for servers to pick him/her out on repeat visits, or to tie together separate visits to different sites, this making tracking and surveillance more difficult. Before a network packet starts its journey, user’s computer chooses a random list of relays and repeatedly encrypts the data in multiple layers, like an onion. Each relay knows only enough to strip off the outermost layer of encryption, before passing what’s left on to the next relay in the list.
- Effort: advanced
TOR Usage
Detects TOR usage, based on the IP address and the destination port (filtered on NTP). TOR is short for The Onion Router, and it gets its name from how it works. TOR intercepts the network traffic from one or more apps on user’s computer, usually the user web browser, and shuffles it through a number of randomly-chosen computers before passing it on to its destination. This disguises user location, and makes it harder for servers to pick him/her out on repeat visits, or to tie together separate visits to different sites, this making tracking and surveillance more difficult. Before a network packet starts its journey, user’s computer chooses a random list of relays and repeatedly encrypts the data in multiple layers, like an onion. Each relay knows only enough to strip off the outermost layer of encryption, before passing what’s left on to the next relay in the list.
- Effort: master
TOR Usage Generic Rule
Detects TOR usage globally, whether the IP is a destination or source. TOR is short for The Onion Router, and it gets its name from how it works. TOR intercepts the network traffic from one or more apps on user’s computer, usually the user web browser, and shuffles it through a number of randomly-chosen computers before passing it on to its destination. This disguises user location, and makes it harder for servers to pick him/her out on repeat visits, or to tie together separate visits to different sites, this making tracking and surveillance more difficult. Before a network packet starts its journey, user’s computer chooses a random list of relays and repeatedly encrypts the data in multiple layers, like an onion. Each relay knows only enough to strip off the outermost layer of encryption, before passing what’s left on to the next relay in the list.
- Effort: master
Telegram Bot API Request
Detects suspicious DNS queries to api.telegram.org used by Telegram Bots of any kind
- Effort: advanced
Event Categories
The following table lists the data source offered by this integration.
| Data Source | Description |
|---|---|
DNS records |
DNS Gateway logs |
In details, the following table denotes the type of events produced by this integration.
| Name | Values |
|---|---|
| Kind | `` |
| Category | network |
| Type | info |
Transformed Events Samples after Ingestion
This section demonstrates how the raw logs will be transformed by our parsers. It shows the extracted fields that will be available for use in the built-in detection rules and hunting activities in the events page. Understanding these transformations is essential for analysts to create effective detection mechanisms with custom detection rules and to leverage the full potential of the collected data.
{
"message": "{\"ApplicationID\":0,\"ColoCode\":\"CDG\",\"ColoID\":533,\"Datetime\":\"2023-02-24T12:12:07Z\",\"DeviceID\":\"\",\"DeviceName\":\"\",\"DstIP\":\"172.12.12.1\",\"DstPort\":23,\"Email\":\"\",\"Location\":\"AWS VM\",\"LocationID\":\"a26c188f-10c2-4333-8ed4-c823fafa06f6\",\"MatchedCategoryIDs\":[],\"MatchedCategoryNames\":[],\"Policy\":\"\",\"PolicyID\":\"\",\"Protocol\":\"udp\",\"QueryCategoryIDs\":[],\"QueryCategoryNames\":[],\"QueryName\":\"ip-111-30-40-252.eu-west-3.compute.internal\",\"QueryNameReversed\":\"internal.compute.eu-west-3.ip-111-30-40-252\",\"QuerySize\":72,\"QueryType\":1,\"QueryTypeName\":\"A\",\"RCode\":3,\"RData\":[],\"ResolvedIPs\":[\"104.18.4.35\",\"104.18.5.35\"],\"ResolverDecision\":\"allowedOnNoPolicyMatch\",\"SrcIP\":\"12.122.186.81\",\"SrcPort\":42424,\"TimeZone\":\"\",\"TimeZoneInferredMethod\":\"noScheduleConfigured\",\"UserID\":\"\"}",
"event": {
"category": [
"network"
],
"dataset": "gateway_dns",
"type": [
"info"
]
},
"@timestamp": "2023-02-24T12:12:07Z",
"cloudflare": {
"ApplicationID": 0,
"ColoCode": "CDG",
"ColoID": 533,
"Location": "AWS VM",
"LocationID": "a26c188f-10c2-4333-8ed4-c823fafa06f6",
"QueryNameReversed": "internal.compute.eu-west-3.ip-111-30-40-252",
"QuerySize": 72,
"QueryType": "1",
"ResolverDecision": "allowedOnNoPolicyMatch",
"TimeZoneInferredMethod": "noScheduleConfigured"
},
"destination": {
"address": "172.12.12.1",
"ip": "172.12.12.1",
"port": 23
},
"dns": {
"question": {
"name": "ip-111-30-40-252.eu-west-3.compute.internal",
"subdomain": "ip-111-30-40-252.eu-west-3.compute",
"type": "A"
},
"resolved_ip": [
"104.18.4.35",
"104.18.5.35"
],
"response_code": "NXDomain"
},
"network": {
"protocol": "dns",
"transport": "udp"
},
"observer": {
"type": "dns",
"vendor": "Cloudflare"
},
"related": {
"hosts": [
"ip-111-30-40-252.eu-west-3.compute.internal"
],
"ip": [
"104.18.4.35",
"104.18.5.35",
"12.122.186.81",
"172.12.12.1"
]
},
"source": {
"address": "12.122.186.81",
"ip": "12.122.186.81",
"port": 42424
}
}
{
"message": "{\"ApplicationID\":0,\"ColoCode\":\"CDG\",\"ColoID\":534,\"Datetime\":\"2023-05-02T16:24:19Z\",\"DeviceID\":\"b72ac397-e5c3-913e-11ed-03face9f2b6b\",\"DeviceName\":\"DESKTOP-ABCDEF\",\"DstIP\":\"162.159.36.1\",\"DstPort\":443,\"Email\":\"john.doe@test.com\",\"Location\":\"loc-01\",\"LocationID\":\"a26c158f-10c2-4223-8ed4-c845fafa06f6\",\"MatchedCategoryIDs\":[],\"MatchedCategoryNames\":[],\"Policy\":\"\",\"PolicyID\":\"\",\"Protocol\":\"https\",\"QueryCategoryIDs\":[21,80],\"QueryCategoryNames\":[\"Security threats\",\"Command and Control & Botnet\"],\"QueryName\":\"commandandcontrolandbotnet.testcategory.com\",\"QueryNameReversed\":\"com.testcategory.commandandcontrolandbotnet\",\"QuerySize\":72,\"QueryType\":65,\"QueryTypeName\":\"HTTPS\",\"RCode\":0,\"RData\":[{\"type\":\"65\",\"data\":\"GmNvbW1hbmRhbmRjb250cm9sYW5kYm90bmV0DHRlc3RjYXRlZ29yeQNjb20AAEEAAQAAADwAOgABAAABAAMCaDIABAAIaBIEI2gSBSMABgAgJgZHAAAAAAAAAAAAaBIEIyYGRwAAAAAAAAAAAGgSBSM=\"}],\"ResolvedIPs\":[],\"ResolverDecision\":\"allowedOnNoPolicyMatch\",\"SrcIP\":\"15.188.186.81\",\"SrcPort\":0,\"TimeZone\":\"\",\"TimeZoneInferredMethod\":\"noScheduleConfigured\",\"UserID\":\"2c46cdd9-92e3-5e5f-b3cf-67965d7c33e3\"}",
"event": {
"category": [
"network"
],
"dataset": "gateway_dns",
"type": [
"info"
]
},
"@timestamp": "2023-05-02T16:24:19Z",
"cloudflare": {
"ApplicationID": 0,
"ColoCode": "CDG",
"ColoID": 534,
"Location": "loc-01",
"LocationID": "a26c158f-10c2-4223-8ed4-c845fafa06f6",
"QueryCategoryIDs": [
21,
80
],
"QueryCategoryNames": [
"Command and Control & Botnet",
"Security threats"
],
"QueryNameReversed": "com.testcategory.commandandcontrolandbotnet",
"QuerySize": 72,
"QueryType": "65",
"RData": [
{
"data": "GmNvbW1hbmRhbmRjb250cm9sYW5kYm90bmV0DHRlc3RjYXRlZ29yeQNjb20AAEEAAQAAADwAOgABAAABAAMCaDIABAAIaBIEI2gSBSMABgAgJgZHAAAAAAAAAAAAaBIEIyYGRwAAAAAAAAAAAGgSBSM=",
"type": "65"
}
],
"ResolverDecision": "allowedOnNoPolicyMatch",
"TimeZoneInferredMethod": "noScheduleConfigured"
},
"destination": {
"address": "162.159.36.1",
"ip": "162.159.36.1",
"port": 443
},
"device": {
"id": "b72ac397-e5c3-913e-11ed-03face9f2b6b"
},
"dns": {
"question": {
"name": "commandandcontrolandbotnet.testcategory.com",
"registered_domain": "testcategory.com",
"subdomain": "commandandcontrolandbotnet",
"top_level_domain": "com",
"type": "HTTPS"
},
"resolved_ip": [],
"response_code": "NoError"
},
"host": {
"hostname": "DESKTOP-ABCDEF",
"name": "DESKTOP-ABCDEF"
},
"network": {
"protocol": "dns",
"transport": "https"
},
"observer": {
"type": "dns",
"vendor": "Cloudflare"
},
"related": {
"hosts": [
"DESKTOP-ABCDEF",
"commandandcontrolandbotnet.testcategory.com"
],
"ip": [
"15.188.186.81",
"162.159.36.1"
]
},
"source": {
"address": "15.188.186.81",
"ip": "15.188.186.81",
"port": 0
},
"user": {
"email": "john.doe@test.com",
"id": "2c46cdd9-92e3-5e5f-b3cf-67965d7c33e3"
}
}
Extracted Fields
The following table lists the fields that are extracted, normalized under the ECS format, analyzed and indexed by the parser. It should be noted that infered fields are not listed.
| Name | Type | Description |
|---|---|---|
@timestamp |
date |
Date/time when the event originated. |
cloudflare.ApplicationID |
number |
ID of the application the domain belongs to (for example, 1, 2). Set to 0 when no ApplicationID is matched. |
cloudflare.ColoCode |
keyword |
The name of the colo that received the DNS query (for example, ‘SJC’, ‘MIA’, ‘IAD’). |
cloudflare.ColoID |
number |
The ID of the colo that received the DNS query (for example, 46, 72, 397). |
cloudflare.Location |
keyword |
Name of the location the DNS request is coming from. Location is created by the customer (for example, ‘Office NYC’). |
cloudflare.LocationID |
keyword |
UUID of the location the DNS request is coming from. Location is created by the customer (for example, ‘7bdc7a9c-81d3-4816-8e56-000000000000’). |
cloudflare.MatchedCategoryIDs |
array |
ID or IDs of category that the domain was matched with the policy (for example, [7,12,28,122,129,163]). |
cloudflare.MatchedCategoryNames |
array |
Name or names of category that the domain was matched with the policy (for example, [‘Photography’, ‘Weather’]). |
cloudflare.Policy |
keyword |
ID of the policy/rule that was applied (if any). |
cloudflare.QueryCategoryIDs |
array |
ID or IDs of category that the domain belongs to (for example, [7,12,28,122,129,163]). |
cloudflare.QueryCategoryNames |
array |
Name or names of category that the domain belongs to (for example, [‘Photography’, ‘Weather’]). |
cloudflare.QueryNameReversed |
keyword |
Query name in reverse (for example, ‘com.example’). |
cloudflare.QuerySize |
number |
The size of the DNS request in bytes (for example, 151). |
cloudflare.QueryType |
keyword |
The type of DNS query (for example, ‘1’, ‘28’, ‘15’, or ‘16’). |
cloudflare.RData |
array |
The rdata objects (for example, {“type”:“5”,“data”:“dns-packet-placeholder…”}). |
cloudflare.ResolverDecision |
keyword |
Result of the DNS query (for example, ‘overrideForSafeSearch’). |
cloudflare.TimeZone |
keyword |
Time zone used to calculate the current time, if a matched rule was scheduled with it. |
cloudflare.TimeZoneInferredMethod |
keyword |
Method used to pick the time zone for the schedule (from rule/ from user ip/ from local time). |
destination.ip |
ip |
IP address of the destination. |
destination.port |
long |
Port of the destination. |
dns.question.name |
keyword |
The name being queried. |
dns.question.type |
keyword |
The type of record being queried. |
dns.resolved_ip |
ip |
Array containing all IPs seen in answers.data |
event.category |
keyword |
Event category. The second categorization field in the hierarchy. |
event.dataset |
keyword |
Name of the dataset. |
event.type |
keyword |
Event type. The third categorization field in the hierarchy. |
host.hostname |
keyword |
Hostname of the host. |
network.protocol |
keyword |
Application protocol name. |
network.transport |
keyword |
Protocol Name corresponding to the field iana_number. |
observer.type |
keyword |
The type of the observer the data is coming from. |
observer.vendor |
keyword |
Vendor name of the observer. |
source.ip |
ip |
IP address of the source. |
source.port |
long |
Port of the source. |
user.email |
keyword |
User email address. |
user.id |
keyword |
Unique identifier of the user. |
For more information on the Intake Format, please find the code of the Parser, Smart Descriptions, and Supported Events here.