Overview of public interfaces for SOC/IT-Security staff

In case of an IT-security incident, emergency oder if a new critical vulnerability (like log4j in December 2021) arises, it is good to be prepared, so you can quickly answer questions like:

• "Are we affected?"
• "Do we use this technology?"
• "Where do we use this vulnerable protocol?"
  
• "To whom is the attack surface exposed to?"
• "Are there mitigations in place?"
• "Is is exploitable without authentication in our setup?"
• "Which is the best place to place a first mitigation?"
  
• etc..

An overview like the following can and will be helpful for your IT-security staff or your Security Operations Center SOC:

System	Internet Facing	Protocol	Authentication	Security	Used Products/Vendors	Logs send to SIEM	Contact Person	Known Weaknesses
Websites	Yes, exposed to all public-ip-addresses	HTTPS (TCP:443) & HTTP (TCP:80 - HTTP 301 Redirect to HTTPS)	None	Web Application Firewall	F5 BigIP LoadBalancer WAF & Apache Container on OpenShift	Yes	Link to CMDB	Websites may contain 3rd party code, SBOM see CMDB
Managed File Transfer	Yes, but limited to dedicated public ip-addresses of partners	HTTPS (TCP:443)	HTTPS Tokens	Web Application Firewall	F5 BigIP LoadBalancer WAF IPSwitch	Yes	Link to CMDB	Runs on VM as appliance, OS might not be hardend from vendor
Citrix	Yes, exposed to all public-ip-addresses	HTTPS (TCP:443)	MFA	Netscaler WAF	Citrix Systems + Okta MFA	Yes	Link to CMDB	NetScaler WAF Ruleset might be out-of-date
Mailserver	Yes, exposed to all public-ip-addresses	SMTP (TCP:25)	None	AntiSpam Mailgatway & AV-Sandbox	Cisco E-Mail Security	Yes	Link to CMDB	Mailgateways run on Hardware, might not be hardended from vendor
SSLVPN S2E	Yes, exposed to all public-ip-addresses	HTTPS (TCP:443)	Mutual TLS Certbased + MFA	Azure DDoS	FortiGate SSLVPN Azure VM + Okta MFA	Yes	Link to CMDB	Possible FortiGate FortiOS SSLVPN Vulnerabilities
M365 ActiveSync	Yes, exposed to all public-ip-addresses	HTTPS (TCP:443)	Mutual TLS Certbased	Azure DDoS	Microsoft 365 + Intunes	Yes	Link to CMDB	Not part of own Vulnerability-Scanner
VPN S2S	Yes, but limited to dedicated public ip-addresses of partners	IPSec UDP:500 & UDP:4500 & ESP	IPsec IKEv2 Certbased Auth	Azure DDoS	FortiGate SSLVPN Azure VM		Link to CMDB	-
DMARC SaaS	Yes, exposed to all public-ip-addresses	DNS (UDP:53), HTTP (TCP:80), HTTPS (TCP:443), SMTP (TCP:25)	None	-	dmarcadvisor.com SaaS	No	Link to CMDB	Not part of own Vulnerability-Scanner
DNS Server	Yes, but limited to dedicated public ip-addresses of partners	DNS (UDP:53 & TCP:53)	None	Azure Network Security Groups	RHEL Bind	Yes	Link to CMDB	-
ISP Routers	Yes, but limited to dedicated public ip-addresses of ISP routers	BGP (TCP:179), BFD, Ping (ICMP:0/8)	BGP MD5 Auth	-	Extreme Networks XOS	Yes	Link to CMDB
etc..	etc..	etc..	etc..	etc..	etc..	etc..	etc..	etc..

 

Of course you can add many more columns like e.g.:

• "SBOM technologys used" (for example: RHEL, Apache Tomcat, OpenSSL, log4j, puppet, ansible, splunk universal forwarder, appdynamics,..)
• Direct links to your Firewall Management System, WAF or SIEM
• "Is it part of our vulnerability scanner?"
• "Is the vulnerability scanner scanning it authenticated?"
• "Is the system/application hardended?"
• and so on :-)

This list will help in case of an IT-security emergency to sort out the first steps in order to mitigate and fix the issue of the public exposed interfaces (like to the internet or to business partners). However this is only one of many steps necessary - always "asume breach" and make sure an attacker controlling a client or server still is unable to spread (unnoticed) in your companies (cloud) network.