Skip to content

Azure Front Door

Overview

Microsoft Azure Front Door is a scalable and secure entry point for fast delivery of your global web applications.

This setup guide describe how to forward events produced by Azure Front Door to SEKOIA.IO.

Benefit from SEKOIA.IO built-in rules and upgrade azure front door with the following detection capabilities out-of-the-box.

SEKOIA.IO x azure front door on ATT&CK Navigator

CVE-2018-11776 Apache Struts2

Apache Struts versions 2.3 to 2.3.34 and 2.5 to 2.5.16 suffer from possible Remote Code Execution when alwaysSelectFullNamespace is true (either by user or a plugin like Convention Plugin) and then: results are used with no namespace and in same time, its upper package have no or wildcard namespace and similar to results, same possibility when using url tag which doesn't have value and action set and in same time, its upper package have no or wildcard namespace.

  • Effort: intermediate
CVE-2018-13379 Fortinet Exploit

Detects the successful exploitation of the Fortinet FortiOS CVE-2018-13379. This CVE is one of the most exploited CVEs since 2018. It is exploited by APT threat actors as well as cybercriminals. The exploitation of this CVE lead an unauthenticated user to get full access to FortiOS system file through SSL VPN via specially crafted HTTP resource requests. The exploit read /dev/cmdb/sslvpn_websession file, that contains login and passwords in (clear/text). An HTTP response status code = 200, means the file was successfully accessed. This vulnerability affects FortiOS 5.6.3 to 5.6.7 and FortiOS 6.0.0 to 6.0.4.

  • Effort: advanced
CVE-2019-0604 SharePoint

Detects the exploitation of the SharePoint vulnerability (CVE-2019-0604)

  • Effort: advanced
CVE-2019-11510 Pulse Secure Exploit

Detects the successful exploitation of the Pulse Secure vulnerability CVE-2019-11510. This CVE is one of the most exploited CVEs since 2019. It is exploited by diverse threat actors, leading sometimes in ransomware deployement. Among these groups: Maze, Conti, Egregor, DoppelPaymer, NetWalker and REvil. But also APT actors such as APT29. The exploitation of this CVE allows a remote, unauthenticated attacker to compromise a vulnerable VPN server. The attacker may be able to gain access to all active users and their plain-text credentials. It may also be possible for the attacker to execute arbitrary commands on each VPN client as it successfully connects to the VPN server. The exploit reads /etc/passwd file to get access to login and passwords in (clear/text). An HTTP response status code = 200, means the file was successfully accessed. This vulnerability affects 8.1R15.1, 8.2 before 8.2R12.1, 8.3 before 8.3R7.1, and 9.0 before 9.0R3.4 products.

  • Effort: elementary
CVE-2019-19781 Citrix Netscaler

Detects CVE-2019-19781 exploitation attempt against Citrix Netscaler, Application Delivery Controller and Citrix Gateway Attack

  • Effort: elementary
CVE-2019-2725 Oracle Weblogic Exploit

Detects the successful exploitation of a deserialization vulnerability in Oracle Weblogic Server, CVE-2019-2725. This vulnerability affects versions 10.X and 12.1.3 of WebLogic that have the components wls9_async_response.war and wls-wsat.war enabled. It is a remote code execution which can be exploited without authentication via HTTP. An HTTP response status code = 202, means the target is vulnerable, the analyst then has to look in depth to check if a webshell has been uploaded or something else has been done.

  • Effort: elementary
CVE-2020-0688 Microsoft Exchange Server Exploit

Detects the exploitation of CVE-2020-0688. The POC exploit a .NET serialization vulnerability in the Exchange Control Panel (ECP) web page. The vulnerability is due to Microsoft Exchange Server not randomizing the keys on a per-installation basis resulting in them using the same validationKey and decryptionKey values. With knowledge of these, values an attacker can craft a special viewstate to use an OS command to be executed by NT_AUTHORITY\SYSTEM using .NET deserialization. To exploit this vulnerability, an attacker needs to leverage the credentials of an account it had already compromised to authenticate to OWA.

  • Effort: elementary
CVE-2020-1147 SharePoint

Detection of SharePoint vulnerability CVE-2020-1147

  • Effort: advanced
CVE-2020-14882 Oracle WebLogic Server

Detects the exploitation of the Oracle WebLogic Server vulnerability (CVE-2020-16952)

  • Effort: advanced
CVE-2020-5902 F5 BIG-IP Exploitation Attempts

Detects the exploitation attempt of the vulnerability found in F5 BIG-IP and described in CVE-2020-5902

  • Effort: elementary
CVE-2021-20021 SonicWall Unauthenticated Administrator Access

Detects the exploitation of SonicWall Unauthenticated Admin Access.

  • Effort: advanced
CVE-2021-20023 SonicWall Arbitrary File Read

Detects Arbitrary File Read, which can be used with other vulnerabilities as a mean to obtain outputs generated by attackers, or sensitive data.

  • Effort: advanced
CVE-2021-21972 VMware vCenter

The vSphere Client (HTML5) contains a remote code execution vulnerability in a vCenter Server plugin. A malicious actor with network access to port 443 may exploit this issue to execute commands with unrestricted privileges on the underlying operating system that hosts vCenter Server. This affects VMware vCenter Server (7.x before 7.0 U1c, 6.7 before 6.7 U3l and 6.5 before 6.5 U3n) and VMware Cloud Foundation (4.x before 4.2 and 3.x before 3.10.1.2). POST request on the following PATH "/ui/vropspluginui/rest/services/uploadova". If in response body (500) the words it has "uploadFile", that means the vCenter is available to accept files via POST without any restrictions.

  • Effort: intermediate
CVE-2021-21985 VMware vCenter

The vSphere Client (HTML5) contains a remote code execution vulnerability due to lack of input validation in the Virtual SAN Health Check plug-in which is enabled by default in vCenter Server. A malicious actor with network access to port 443 may exploit this issue to execute commands with unrestricted privileges on the underlying operating system that hosts vCenter Server. This affects VMware vCenter Server (7.0 before 7.0 U2b, 6.7 before 6.7 U3n and 6.5 before 6.5 U3p) and VMware Cloud Foundation (4.x before 4.2.1 and 3.x before 3.10.2.1).

  • Effort: intermediate
CVE-2021-22893 Pulse Connect Secure RCE Vulnerability

Detects potential exploitation of the authentication by-pass vulnerability that can allow an unauthenticated user to perform remote arbitrary file execution on the Pulse Connect Secure gateway. It is highly recommended to apply the Pulse Secure mitigations and seach for indicators of compromise on affected servers if you are in doubt over the integrity of your Pulse Connect Secure product.

  • Effort: intermediate
CVE-2021-26855 Exchange SSRF

Detects the exploitation of ProyxLogon vulerability on Exchange servers.

  • Effort: advanced
CVE-2021-34473 ProxyShell Attempt

Detects CVE-2021-34473 ProxyShell attempt against Microsoft Exchange Server, Remote Code Execution Vulnerability.

  • Effort: advanced
CVE-2021-41773 Apache 2.4.49 Path Traversal

Detects successful exploitation of the Apache Path Traversal CVE-2021-41773.

  • Effort: advanced
CVE-2021-43798 Grafana Directory Traversal

Grafana version 8.x has a 0day arbitrary file read (with no fix yet) based on a directory traversal vulnerability

  • Effort: intermediate
Cobalt Strike HTTP Default GET beaconing

Detects GET HTTP queries from known Cobalt Strike beacons (source code 4.3)

  • Effort: advanced
Cobalt Strike HTTP Default POST Beaconing

Detects POST HTTP queries from known Cobalt Strike beacons (source code 4.3)

  • Effort: advanced
Covenant Default HTTP Beaconing

Detects potential Covenant communications through the user-agent and specific urls

  • Effort: intermediate
FoggyWeb HTTP Default GET/POST Requests

Detects GET or POST request pattern observed within the first FoggyWeb campaign detected by Microsoft.

  • Effort: advanced
GitLab CVE-2021-22205

Detects GitLab vulnerability CVE-2021-22205 exploitation success. It allows an attacker to do some remote code execution with user git. The HTTP return code 422 indicates a successfull exploitation.

  • Effort: intermediate
LokiBot Default C2 URL

Detects default C2 URL for trojan LokiBot

  • Effort: elementary
Possible Malicious File Double Extension

Detects request to potential malicious file with double extension

  • Effort: elementary
Potential Bazar Loader User-Agents

Detects potential Bazar loader communications through the user-agent

  • Effort: elementary
Potential Lemon Duck User-Agent

Detects LemonDuck user agent. The format used two sets of alphabetical characters separated by dashes, for example "User-Agent: Lemon-Duck-[A-Z]-[A-Z]".

  • Effort: elementary
Potential LokiBot User-Agent

Detects potential LokiBot communications through the user-agent

  • Effort: intermediate
Privilege Escalation Awesome Scripts (PEAS)

Detect PEAS privileges escalation scripts and binaries

  • Effort: elementary
Raccoon Stealer 2.0 Legitimate Third-Party DLL Download URL

Detects Raccoon Stealer 2.0 malware downloading legitimate third-party DLLs from its C2 server. These legitimate DLLs are used by the information stealer to collect data on the compromised hosts.

  • Effort: elementary
SEKOIA.IO Intelligence Feed

Detect threats based on indicators of compromise (IOCs) collected by SEKOIA's Threat and Detection Research team.

  • Effort: elementary
Suspicious Download Links From Legitimate Services

Detects users clicking on Google docs links to download suspicious files. This technique was used a lot by Bazar Loader in the past.

  • Effort: elementary
Suspicious URI Used In A Lazarus Campaign

Detects suspicious requests to a specific URI, usually on an .asp page. The website is often compromised.

  • Effort: intermediate
TrevorC2 HTTP Communication

Detects TrevorC2 HTTP communication based on the HTTP request URI and the user-agent.

  • Effort: elementary

Event Categories

The following table lists the data source offered by this integration.

Data Source Description
Web logs Microsoft Azure Front Door act as a proxy and provide associated traffic logs
Web application firewall logs Microsoft Azure Front Door protect web application with its web application firewall and provide associated traffic logs

In details, the following table denotes the type of events produced by this integration.

Name Values
Kind event
Category network
Type info

Event Samples

Find below few samples of events and how they are normalized by SEKOIA.IO.

{
    "message": "{\"time\":\"2022-08-29T15:03:25.4715017Z\",\"resourceId\":\"/SUBSCRIPTIONS/XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/RESOURCEGROUPS/YYYYYYYYYYYYYYYYY/PROVIDERS/MICROSOFT.CDN/PROFILES/ZZZZZZZZZZZZZZZ\",\"category\":\"FrontDoorAccessLog\",\"operationName\":\"Microsoft.Cdn/Profiles/AccessLog/Write\",\"properties\":{\"trackingReference\":\"0PdUMYwAAAAAA35SK7dpvSZxm/Y92xsH7UEFSMjAxMDgwMzg1MDQ5ADkxZjFmYTAyLWMzZGEtNDBlMi04ZWM2LWQ0OTQ1OWJiNzc5OQ==\",\"httpMethod\":\"GET\",\"httpVersion\":\"1.1.0.0\",\"requestUri\":\"http://example.1.azurefd.net:80/\",\"requestBytes\":\"109\",\"responseBytes\":\"221\",\"userAgent\":\"curl/7.77.0\",\"clientIp\":\"1.2.3.4\",\"socketIp\":\"1.2.3.4\",\"clientPort\":\"53170\",\"timeToFirstByte\":\"0.002\",\"timeTaken\":\"0.002\",\"requestProtocol\":\"HTTP\",\"securityProtocol\":\"\",\"endpoint\":\"example.1.azurefd.net\",\"routingRuleName\":\"example.1.azurefd.net\",\"rulesEngineMatchNames\":[\"DefaultHttpsRedirectRule\"],\"httpStatusCode\":\"307\",\"httpStatusDetails\":\"307\",\"pop\":\"PAR\",\"cacheStatus\":\"CONFIG_NOCACHE\",\"ErrorInfo\":\"NoError\",\"hostName\":\"example.1.azurefd.net\",\"originUrl\":\"N/A\",\"originIp\":\"N/A\",\"originName\":\"N/A\",\"referer\":\"\",\"clientCountry\":\"France\",\"domain\":\"example.1.azurefd.net:80\",\"securityCipher\":\"\"}}\n",
    "event": {
        "kind": "event",
        "category": [
            "network"
        ],
        "type": [
            "info"
        ],
        "action": "Microsoft.Cdn/Profiles/AccessLog/Write",
        "dataset": "access"
    },
    "@timestamp": "2022-08-29T15:03:25.4715017Z",
    "observer": {
        "vendor": "Microsoft",
        "product": "Azure Front Door",
        "hostname": "example.1.azurefd.net"
    },
    "source": {
        "ip": "1.2.3.4",
        "port": 53170,
        "address": "1.2.3.4"
    },
    "http": {
        "request": {
            "method": "GET",
            "bytes": 109
        },
        "response": {
            "status_code": 307,
            "bytes": 221
        },
        "version": "1.1"
    },
    "url": {
        "original": "http://example.1.azurefd.net:80/",
        "domain": "example.1.azurefd.net",
        "top_level_domain": "net",
        "subdomain": "example.1",
        "registered_domain": "azurefd.net",
        "port": 80,
        "path": "/",
        "scheme": "http"
    },
    "user_agent": {
        "original": "curl/7.77.0"
    },
    "network": {
        "protocol": "HTTP"
    },
    "azure_front_door": {
        "resource_id": "/SUBSCRIPTIONS/XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/RESOURCEGROUPS/YYYYYYYYYYYYYYYYY/PROVIDERS/MICROSOFT.CDN/PROFILES/ZZZZZZZZZZZZZZZ",
        "category": "FrontDoorAccessLog"
    },
    "related": {
        "hosts": [
            "example.1.azurefd.net"
        ],
        "ip": [
            "1.2.3.4"
        ]
    }
}
{
    "message": "{\"time\":\"2022-08-28T13:01:19.0427677Z\",\"resourceId\":\"/SUBSCRIPTIONS/XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/RESOURCEGROUPS/YYYYYYYYYYYYYYYYY/PROVIDERS/MICROSOFT.CDN/PROFILES/ZZZZZZZZZZZZZZZ\",\"category\":\"FrontDoorHealthProbeLog\",\"operationName\":\"Microsoft.Cdn/Profiles/FrontDoorHealthProbeLog/Write\",\"properties\":{\"healthProbeId\":\"A07EBB1B3DF34A71A8AC75CBA4C33607\",\"POP\":\"BUD\",\"httpVerb\":\"HEAD\",\"result\":\"OriginError\",\"httpStatusCode\":\"301\",\"probeURL\":\"http://example.azurestaticapps.net:80/\",\"originName\":\"example.azurestaticapps.net\",\"originIP\":\"1.2.3.4\",\"totalLatencyMilliseconds\":\"97\",\"connectionLatencyMilliseconds\":\"24\",\"DNSLatencyMicroseconds\":\"48133\"}}",
    "@timestamp": "2022-08-28T13:01:19.0427677Z",
    "source": {
        "address": "1.2.3.4",
        "ip": "1.2.3.4"
    },
    "related": {
        "ip": [
            "1.2.3.4"
        ]
    },
    "event": {
        "kind": "event",
        "category": [
            "network"
        ],
        "type": [
            "info"
        ],
        "dataset": "health",
        "action": "Microsoft.Cdn/Profiles/FrontDoorHealthProbeLog/Write"
    },
    "observer": {
        "vendor": "Microsoft",
        "product": "Azure Front Door"
    },
    "http": {
        "request": {
            "method": "HEAD"
        },
        "response": {
            "status_code": 301
        }
    },
    "url": {
        "original": "http://example.azurestaticapps.net:80/",
        "path": "/",
        "port": 80,
        "domain": "example.azurestaticapps.net",
        "registered_domain": "azurestaticapps.net",
        "subdomain": "example",
        "top_level_domain": "net",
        "scheme": "http"
    },
    "azure_front_door": {
        "resource_id": "/SUBSCRIPTIONS/XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/RESOURCEGROUPS/YYYYYYYYYYYYYYYYY/PROVIDERS/MICROSOFT.CDN/PROFILES/ZZZZZZZZZZZZZZZ",
        "category": "FrontDoorHealthProbeLog",
        "health_probe_id": "A07EBB1B3DF34A71A8AC75CBA4C33607"
    }
}

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.
azure_front_door.cache_status keyword The status code of the cache of the CDN
azure_front_door.category keyword The category of the event
azure_front_door.health_probe_id keyword The identifier of the health probe
azure_front_door.resource_id keyword The identifier of the Microsoft Azure resource
azure_front_door.route_name keyword The name of the route that the request matched
azure_front_door.rule.names keyword The names of rules that handled the request
error.code keyword Error code describing the error.
event.action keyword The action captured by the event.
event.category keyword Event category. The second categorization field in the hierarchy.
event.kind keyword The kind of the event. The highest categorization field in the hierarchy.
event.type keyword Event type. The third categorization field in the hierarchy.
http.request.bytes long Total size in bytes of the request (body and headers).
http.request.method keyword HTTP request method.
http.request.referrer keyword Referrer for this HTTP request.
http.response.bytes long Total size in bytes of the response (body and headers).
http.response.status_code long HTTP response status code.
http.version keyword HTTP version.
network.protocol keyword Application protocol name.
observer.hostname keyword Hostname of the observer.
observer.product keyword The product name of the observer.
observer.vendor keyword Vendor name of the observer.
source.ip ip IP address of the source.
source.port long Port of the source.
tls.cipher keyword String indicating the cipher used during the current connection.
tls.version keyword Numeric part of the version parsed from the original string.
tls.version_protocol keyword Normalized lowercase protocol name parsed from original string.
url.original wildcard Unmodified original url as seen in the event source.
user_agent.original keyword Unparsed user_agent string.

Configure

Prerequisites

To forward events to SEKOIA.IO, create an Event hub namespace and an Event hub with a consumergroup.

Once created, in your EventHubs, go to Setting > Shared access policies. Create a new policy with the option Listen then copy the Connection string-primary key.

Create a Storage accounts or use an existing one. Go to Data storage > containers and create a new container. Then go to Security + networking > Access keys and copy the key1 Connection string

Configure Azure Front door to stream its logs to the EventHub with this guide.

Create the intake

Go to the intake page and create a new intake from the format Azure Front Door.

Pull events

Go to the playbook page and create a new playbook with the Consume Eventhub messages.

Set up the trigger configuration with the EventHub's Connection string-primary key, the hub name, the consumer group, the storage's Connection string-primary key and the container name.

Start the playbook and enjoy your events.

Further Readings