Sudo or SuDon't: Manage Your Privileged Command Execution and Sudo Policies

MANAGING PRIVILEGED ACCESS

Managing privilege in the enterprise server infrastructure can be a real challenge. For starters, Linux and Unix system administrators will need root level authority at times to do their jobs. Systems operations staff such as DBAs will also need periodic database and application account authority. And last, security administrators will need to protect the environment. Adding to the challenge, the security administrator role does not even exist in many organizations that have grown their infrastructure quickly.

The sudo utility offers a solution to delegate root authority for OS administration commands (for example, “backup”) specific to the task without giving up full root access. It can also delegate applications or DBA authority to operations staff without giving up, say, the “oracle” account.

Sudo is most commonly managed with a policy text file local to each and every server, which can become a change management nightmare. In many instances, we find groups of policies allowing system administrators full root access… often without further challenge for authentication. At this point, the security administrator has effectively relinquished control of the root account and put the trust in the system administrator due to the fact that the administrator can now change the policy herself. Root authority is at the discretion of the administrator, and often influenced by help desk tickets in the day-job which tend to be more operationally focused than security minded.

In many cases, after a server has been commissioned and loaded, updates to sudo policies are unknown thereafter and not effectively audited by the security administrator nor reported to the line-of-business System Owners as ongoing risks to business data.

With more detailed inspection, the sudo configuration can also allow a lot more access than originally intended. Many system commands allow a user to ‘shell out’ to run commands with the effective user ID of the original command. Common examples include: vi, more, less, tee, man, awk, sed, find. Commands and management scripts for other applications, database, and programming environments (irb, l;ua, perl, python Sql*Net, ruby) have similar problems. While a sudo rule may initially appear to grant limited scope and authority, in reality, they may have left root, application, or database access wide open on the server OS.

SCALING AND AUTOMATION

Maintaining a consistent security policy on a large number of servers can also become a huge burden to the security administrator. Configuration tools like Puppet can mitigate the problem to some degree, but the policy is vulnerable to sudo file updates in the same way between configuration updates, leaving a window of opportunity to plant back-door mechanisms that circumvent the authorized security policy.

IS THERE A BETTER WAY? "SUDO OR SUDON'T?"

Powertech Identity & Access Manager (BoKS) offers a solution by defining and enforcing privileged command execution security policy in a central database. The policy for an individual cannot be changed even when an administrator or operations user has been granted root, application or dba access on a server. With Identity & Access Manager (BoKS), the security administrator maintains the security policy, and can grant the system administrator or operator the appropriate level of privilege to do her job, maintaining a clear segregation of duties. 

Centralizing the security configuration eases the pain of maintaining a consistent policy across the enterprise so that even large environments become manageable. Privilege escalation is centrally logged and offers keystroke logging where appropriate, making audit and operations reporting trivial.

GUT CHECK

Sudo can be an effective tool when used properly. Sadly, improper use is far too common either from inappropriate or ineffective configuration definitions, or simply due to the overwhelming task of maintaining the still-growing server environment with limited tools and over-extended administration and operations staff. Identity & Access Manager (BoKS) can enable a security administrator to effectively manage least-privilege with better security, greater efficiency, and centralized auditing and logging for even the largest enterprise organizations.