Showing posts with label SANS. Show all posts
Showing posts with label SANS. Show all posts

Friday, November 7, 2014

Security Corner: Centrify and SANS Critical Security Controls - A Near Perfect Fit (4/5)

This is part 4 of the series on leveraging Centrify to implement SANS Critical Security controls - Section 12: "Controlled use of Administrative Privileges".  (Also relates to PCI DSS 10.2)

CSC 12-11  Configure systems to issue a log entry and alert when unsuccessful login to an administrative account is attempted.

Why should you do this?
This is a detective control.  You can't control what you're not tracking.  Security operations typically leverage log aggregation technologies that tap into the native OS log facilities and centralize all this information into a centralized logging infrastructure that may or may not offer intelligence.

What is the typical approach?
On Windows:  Harvest and mine of the Windows event logs.  Surprisingly, a lot of outfits are not auditing the logon/log-off success/failure events.
On UNIX:  Harvest and mine the UNIX syslogs.

What is the real challenge for organizations?
Data vs. Noise.   How can organizations reconcile all the sources of data into meaningful information?  This is not Centrify's main capability, but it can certainly help by requiring meaningful data (e.g. change control/authorization numbers) and if all logs fail, there's always the session capture/replay capability.

Centrify's enhancers:
  • Use what's native:  Uses syslog and event logs.  Unix logon/logoff success or failure are logged in the security log of the domain controller if configured by the Windows sysadmin.
  • Enhance to differentiate the data from the noise:  Centrify can be configured to require reference information upon elevation, for example, change control number.
  • Contextualize with DirectAudit to "clear the noise":  Enterprise Edition offers session capture and replay for both UNIX, Linux and Windows.
  • Adding DirectAudit (Enterprise Edition) exceeds the requirements of PCI DSS 10.2 "reconstruct events"
Have a look:

How privileged elevation is logged (syslog) and recorded with Centrify on UNIX:

How with the Centrify dzdo validator, you can add more meaningful data to privilege elevation

How privileged elevation is logged (eventlog) and recorded with Centrify on Windows:

Wednesday, November 5, 2014

Security Corner: Centrify and SANS Critical Security Controls - A Near Perfect Fit (3/5)

This is part 3 of the series on leveraging Centrify to implement SANS Critical Security controls - Section 12: "Controlled use of Administrative Privileges".

CSC 12-7 Utilize access control lists to ensure that administrative accounts are used only for system administration activities, and not for reading e-mail, composing documents, or surfing the Internet. Web browsers and e-mail clients especially must be configured to never run as administrator.

Why should you do this?
To limit the exposure of administrative accounts to malware.

What is the typical approach?
On Windows:  Two sets of accounts are given to administrators,  a "dash-a" account and a normal account.  On the server side, to access the internet there's an air gap or the proxy server does not allow the servers or the "dash-a" account to go out to the internet.  The IE Enhanced Security mode is enforced.

On UNIX:  Systems are crippled from internet access or GUIs.  The email/surfing computer is different from the server systems.

What is the real challenge for organizations?
Human nature - people find ways to go around this, especially in the process of doing their actual jobs.  In the times of "knowledge on demand" having an internet browser to consult FAQs and community boards is very common.

Centrify's enhancers:
It's not all about just giving separate accounts, but being able to establish additional controls, like scope of systems, types of roles, privilege effectiveness, logon experience and flexible assignments.



CSC 12-10 Configure systems to issue a log entry and alert when an account is added to or removed from a domain administrators' group, or when a new local administrator account is added on a system.

Why should you do this?
At basic level this is a detective control, all administrative access should be traced back to an approval, otherwise this is misuse or a data-breach.

What is the typical approach?
Log aggregation.  Logs from multiple systems are sent to an enterprise security operations dashboard.

What is the real challenge for organizations?
Log aggregation lends itself for NOISE, then the log aggregation needs to be complemented by a data mining engine;  this is all to make sure that what's happening out there is authorized.

Centrify's enhancers:
  • A Centrify deployment limits the local root or administrator account to break-glass situations.  They are not needed.
  • Centrify (without any modification) augments log aggregation.  Therefore, the existing collection mechanisms can have richer data.
  • Plus, Centrify reporting shows you what are the AD principals that grant the administrative roles, if things are tied to a Workflow or an IDM, anything that is not there by way of approvals will be identified quickly or rolled back.
  • Plus Centrify DirectAudit provides the ability to view or audit who makes changes to the governance model.

Short video:

Friday, October 31, 2014

Security Corner: Centrify and SANS Critical Security Controls - A Near Perfect Fit (2/5)

This is the continuation of the series on leveraging Centrify to implement SANS Critical Security controls - Section 12: "Controlled use of Administrative Privileges".

CSC 12-3Configure all administrative passwords to be complex and contain letters, numbers, and special characters intermixed, and with no dictionary words present in the password. Pass phrases containing multiple dictionary words, along with special characters, are acceptable if they are of a reasonable length.

CSC 12-5Ensure that all service accounts have long and difficult-to-guess passwords that are changed on a periodic basis, as is done for traditional user and administrative passwords.

CSC 12-8Through policy and user awareness, require that administrators establish unique, different passwords for their administrative and non-administrative accounts. Each person requiring administrative access should be given his/her own separate account. Users should only use the Windows "administrator" or UNIX "root" accounts in emergency situations. Domain administration accounts should be used when required for system administration instead of local administrative accounts.

CSC 12-9 Configure operating systems so that passwords cannot be re-used within a timeframe of six months.

Why should you do this?
Because the password policy for admin accounts should be a step-up from regular users given that they hold the keys to the kingdom. 

What is the typical approach?
On Unix:  cracklib PAM module.
On Windows:  group policy.

What is the real challenge for organizations?
Human nature - sysadmins love their root or administrator accounts given their inherent mistrust in software, and unfortunately vendors promote fragmentation. 

Centrify's enhancers:
It's the solution that can accomplish this with true RBAC (allowing the administrative accounts to be put away) plus the tight AD integration with Group Policies (and support for fine-grained password policies).  In addition, Centrify's resiliency truly makes sure that the root or administrator account are only needed in emergency situations.


In UNIX - privilege elevation using Centrify-enhanced sudo (no sudoers) - DirectAuthorize (DZ)
In Windows - privilege elevation with the Centrify agent for Windows (DZ Win)


CSC 12-4Before deploying any new devices in a networked environment, change all default passwords for applications, operating systems, routers, firewalls, wireless access points, and other systems to have values consistent with administration-level accounts.

Why should you do this?
Anyone that has had a Linksys router knows the answer to this.  In UNIX/Linux, there's too much reliance on the root account or the switch user command.  Local administrator in Windows is treasured by Windows admins.

What is the typical approach?
Unfortunately, in a lot of environments there's too much sharing of these accounts.  TACACs, RADIUS and password vaults help with network appliances.

What is the real challenge for organizations?
Human nature.  A Unified approach for these accounts like a password vault is typically the right solution.

Centrify's enhancers:
Due to the true RBAC and privilege elevation methods employed by Centrify, organizations can decrease their costs in password vault user licensing costs, by just leveraging it for non-human admin accounts, while the rest of the population uses RBAC.  The end-to-end nature and resilience mechanisms, makes it more efficient to align with regulatory requirements without a single point of failure.  In UNIX, single-user-mode or Windows safe mode without network will be the only instances in which these accounts are needed.

No need to check-out the keys to the kingdom each time the root, or administrator accounts are needed.
  • Tied to your identity infrastructure (Active Directory)
  • True Role-based access
  • Minimal process impact
  • Increased accountability using the native tools (syslog/event viewer)
  • Extensible to session capture and replay
Tried and true AAA.

CSC 12-6Passwords should be hashed or encrypted in storage. Passwords that are hashed should be salted and follow guidance provided in NIST SP 800-132 or similar guidance. Files containing these encrypted or hashed passwords required for systems to authenticate users should be readable only with super-user privileges.

Why should you do this?
There was a time in the security discipline in which encryption was thought to be the solution;  time and different attack vectors have proven this to be wrong; however, encryption in transit and encryption at rest are a must.  There's an arms race going on because although algorithms are strong, Moore's law, virtualization and well-funded and motivated agents are lurking.

What is the typical approach?
Rely on the OS, Directory or the appliance.  Fortunately Microsoft has this very-well documented.

What is the real challenge for organizations?
Human nature, again  It doesn't matter how hard your encryption is if credentials are shared or clear-text passwords are used in scripts or other facilities.

Centrify's enhancers:
However, the bullets above are just marketing speak if we don't back-it up with examples:
  • Kerberized tools:  install.sh adjoin, adleave, adkeytab, adcert, dzdo + more are all Kerberized, which means no need to actually store passwords.  The Hadoop and MongoDB examples illustrate practical use.
  • Microsoft CA PKI client:  Use Certificates in your Unix, Linux, Mac systems.
  • Extend it to your HTTP, Java, SAP or DB2 needs.

Why even have the problem when you can completely avoid it?

Wednesday, October 29, 2014

Security Corner: Centrify and SANS Critical Security Controls - A Near Perfect Fit (1/5)

Background

One of our prospects looking at the Centrify privileged elevation tool for Windows, just highlighted to me that Server Suite is very well-aligned with the SANS Critical Security Controls Section 12: "Controlled use of Administrative Privileges" so I decided to take a deeper look.  We will cover 2 each post until we have the 14 topics explored.

Controlled use of Administrative Privileges


CSC 12-1Minimize administrative privileges and only use administrative accounts when they are required. Implement focused auditing on the use of administrative privileged functions and monitor for anomalous behavior.

Why should you do this?
Because the more somebody uses a privileged account the highest risk of malware being executed with elevation, more exposure to attacks like pass-the-hash attack, etc. 

What is the typical approach?
On Unix:  sudo, password vaults or RBAC
On Windows:  dash-a accounts, password vaults or RBAC

What is the real challenge for organizations?
Well, sudo is simple, proven but a pain, PVs just give out the keys to the kingdom in a controlled way - great for appliances BTW, and RBAC is hard to implement given that it typically requires multiple solutions.

Centrify to the Rescue:  Centrify Server Suite offers a serverless, cross-platform Unix, Linux and Windows based solution that provides access governance with RBAC leveraging AD.


End Result: The ability to limit access, control privileges (no giving out the keys to the kingdom) and reusing processes, cross platform, using existing technology and infrastructure.  This was explored in the 10-minutes PCI 7 challenge:.




CSC 12-2Use automated tools to inventory all administrative accounts and validate that each person with administrative privileges on desktops, laptops, and servers is authorized by a senior executive.

Why should you do this?
This is all about keeping track and being able to attest who approved the type of access that users have.  It's also an administrative preventative control.  This is not limited to domain accounts but local accounts as well

What is the typical approach?
The solution to this is basically workflow.  Unfortunately, simple workflow engines are hard to come by, or they are tied to a monster solution.  Scripts are popular as well.

What is the real challenge for organizations?
This should be relatively simple, but vendors don't make this easy.  Surprisingly PV vendors do a good job due to the appliance/proxy based nature of their solutions. Go to the vault, request access, approver gets notified, approves/denies, then the access is granted/denied.  Great for break/fix.

How Centrify helps?  Although Centrify does not provide workflow capabilities today (wink);  it makes it very easy for any IdM or workflow engine to perform the functions upstream.  Since the process boils down to AD groups and any decent workflow engine can do this, then the solution looks like this:


Utilities:  Automatic provisioning and role assignment is often achieved with ZPA.  This post and video cover a basic design:



In the next post we'll continue with the list.