Audit and Control of Enterprise Vulnerability Management. Grant Johnson, Technical Account Manager

Transcription

1 Audit and Control of Enterprise Vulnerability Management Grant Johnson, Technical Account Manager Phoenix May 14, 2014

2 Key Elements of EVM IT Asset Inventory and Control Risk-based Vulnerability Management & Strategy Scan Management and Strategy Vulnerability Tracking and Closure Scan Exclusion/Exception Process Some Best Practices Some Reference and Resources 2

3 Some quick thoughts Lifecycle of a Vulnerability Scan I added some key things to remember as you are planning the audit approach Verification Vulnerability life Cycle Identification & Reporting There are some suggested audit steps Patching & Configuration Ticketing A risk rating for context an ongoing continuous cycle 3

4 IT Asset Inventory & Control

5 IT Asset Inventory and Control CMDB- Configuration Management Database Or IT Asset Inventory You cannot manage that which you do not track 5

6 IT Asset Inventory and Control Things to Know: Inventories are VITAL to ensure vulnerability scan coverage is complete These inventories are difficult to maintain and are error prone Server Inventory should be tested or spot-checked for completeness Information could include, server, I.Ps, rack location, applications, owner, data risk, etc.. Maintenance for the inventories are usually a collective effort, don t shoot the messenger Audit Steps: List-to-Floor, Floor-to-List inventory check (accuracy & completeness) Inspect data center inventory for proper labeling on devices Map the environment [Tool based] and compare with inventory list 6 Risk Rating

7 Scan Management and Strategy

8 Scan Management & Strategy Scan Intervals - There should be a controlled process that determines scan frequency and reporting frequency. Be observant of possible gaps created by intervals Scan Metrics Vulnerability scanning can be affected by network outages, firewalls, traffic management, DNS Errors etc. Scans require administrative access that can affect scan completeness and accuracy. Good vulnerability management will have a method of tracking scan success Configuration Management The process by which management defines permissible services, settings and applications - e.g. Should FTP be allowed for servers within the DMZ? A solid hardening process will save hours of vulnerability management and reduce risk. 8 Risk Rating

9 Scan Management & Strategy What to scan Pretty much everything. Here is the short list: Web Servers: Apache, Microsoft ISS; iplanet; Lotus Domino; IpSwitch; Zeus; full support for virtual hosting. SMTP/POP Servers: Sendmail; Microsoft Exchange; LotusDomino; Netscape Messaging Server; QMail. FTP Servers: IIS FTP Server; WuFTPd; WarFTPd. Firewalls: Check Point Firewall-1/VPN-1 and NG; Cisco PIX; Juniper NetScreen; Gauntlet; CyberGuard; Raptor. Databases: Oracle; Sybase; MS SQL; PostgreSQL; MySQL. ecommerce: Icat; EZShopper; Shopping Cart; PDGSoft; Hassan Consulting Shopping; Perishop. LDAP Servers: Netscape; IIS; Domino; Open LDAP. Load Balancing Servers: Cisco CSS, Alteon, F5 BIG IP; IBM Network Dispatcher; Intel Routers; Administrable. Switches and Hubs: Cisco; 3Com; Nortel Networks; Cabletron; Lucent; Alcatel. Wireless Access Points: Cisco; 3Com; Symbol; Linksys; D-Link; Netgear; Avaya; Apple Airport; Nokia; Siemens.d 9

10 Scan Management & Strategy Things to Know: Scan frequency should match the risk of loss associated with the data and system Frequency can range from monthly/bi monthly to continuous Vulnerabilities garner differing levels of Risk. e.g. associated with malware, remotely executable etc.. Scan signature should be VERY current Auto-update is recommended Approach needs to comply with local and national laws Audit Steps: Select a sample of high-risk servers and determine the last-scanned date and is it within the stated goals of the scan strategy Does the scan interval meet regulatory requirements? Review the process for updating the scan signature and scan completeness Manual updates should be fully justified and tested. Determine if any critical tests are excluded from review - Management should justify Determine if Scan success and results are tracked Are hardening guidelines published and followed How? 10 Risk Rating

11 Risk Based Vulnerability Strategy

12 Risk Based Vulnerability Strategy Three Broad Risks to consider.. Outward and Customer- Facing systems need to be prioritized Public Network These systems should be clearly identifiable Management should have a Defined data classification scheme There should be a concise inventory of systems that host, store and process sensitive data 12

13 Risk Based Vulnerability Strategy How do you priorities which high severity findings to fix first? Prioritize vulnerabilities when known exploits are published by third party vendors and/or publicly available sources. Good VM tools constantly correlate exploitability information from real-time feeds to provide up to date references to exploits and related security resources. Look for malware associated vulnerabilities. Vulnerability scanners correlate malware information with vulnerabilities when malware threats for vulnerabilities are published within the Trend Micro Threat Encyclopedia or other authoritative sources Prioritize the vulnerability can be detected using remote (unauthenticated) scanning. Begin with vulnerabilities that are fixable with a patch that is currently available from the vendor. In Summary: Start with -High exposure systems Public facing - Systems that hold or use High risk data - Fix the High probably/high severity, patchable vulnerabilities 13

14 Risk Based Vulnerability Strategy The VM solution needs to provide the capability to scan for and fix vulnerabilities in a broad range of categories, including: Back Doors and Trojan Horses (bypass authentication systems). Brute force attacks (defies cryptography by systematically trying different keys). CGI (exploits the Common Gateway Interface). Databases. DNS and Bind (exploits Domain Name Services). E-commerce applications. File sharing. File Transfer Protocol. Firewalls. 14

15 Risk Based Vulnerability Strategy Things to Know: Management needs to have a plan to identify and priorities the systems that are subject to vulnerability management. It is very difficult if not impossible to fix all or All Sev 4s and 5s Risk differs from server to server depending on Host data, internet facing, etc. Vulnerabilities garner differing levels of threat and should match the patch cycles Start with the fixable vulnerabilities Audit Steps: Review system risk assessment used to identify HIGH risk systems based on Data sensitivity Review network diagrams used to track externally facing systems Ensure HIGH risk systems are scanned in accordance with policy guidelines Review action plans associated with high severity vulnerabilities 15 Risk Rating

16 Vulnerability Tracking and Closure

17 Vulnerability Tracking and Closure Things to Know: There needs to be a manageable, measurable process to track Vulnerabilities Many companies use ticketing systems There will ALWAYS be exceptions to a policy Need to ensure that exceptions are approved and reviewed at a regular interval Vulnerability ageing is a commonly applied metric Audit Steps: Ensure system ownership is properly documented lines of responsibility for security are properly assigned Is there a process in place to escalate overdue or unpatched systems outside of policy- Test by reviewing scan results Does management monitor aging of vulnerabilities of a system 17 Risk Rating

18 Scan Exclusions and Exception Process

19 Scan Exclusions & Exceptions Some systems maybe appropriately excluded from vulnerability scanning!! Possible Scenarios Process networks Air-Gaped networks Low risk, untrusted systems Be VERY wary of this justification Smart Equipment (oops..) System is being DE installed System cannot tolerated a scan without interruption 19 Risk Rating

20 Scan Exclusion/Exceptions Things to Know: High risk in that these are permanent blind spots for vulnerabilities to hide There are some systems that should be excluded the need for security scanning does not outweigh business use. Scan-caused crashed can be an indication of a misconfigured system Exceptions to scanning should be documented/approved and subject to regular review Audit Steps: Is there a formal, documented process to exclude a system from scanning? Are scanning exceptions reviewed at a regular interval? Select a sample of excluded hosts and determine if the hosts Determine if there are action plans in place to remediate older systems and subject them to future vulnerability scans 20 Risk Rating

21 Some Best Practices

22 Some Best Practices Vulnerability Management is best driven at the CISO level Metrics should be designed to give C level management something to manage to number of days to close vulnerabilities scan coverage as a % authentication % Patch Metrics and Configuration Management dashboards have been found to be more effective that voluminous reports of high severity vulnerabilities Be cautious when recommending automatic ticketing for new vulnerabilities 22 Risk Rating

23 Some Good References- free 23

24 Free Services at your Fingertips 24

25 Thank You