EventTracker and Shellshock

Summary:

  • Shellshock (also known as Bashdoor) CVE-2014-6271 is a security bug in the Linux/Unix Bash shell.
  • EventTracker v 6.x, v7.x is NOT vulnerable to Shellshock as these products are based on the Microsoft Windows platform.
  • ETIDS and ETVAS which are offered as options of the SIEM Simplified service, are vulnerable to Shellshock, as these solutions are based on CentOS v6.5. Below are the links relevant to this vulnerability.
  • If you subscribe to ETVAS and/or ETIDS, the EventTracker Control Center has already initiated action to patch this vulnerability on your behalf. Please contact ecc@eventtracker.com with any questions.

Details:

Shellshock (also known as Bashdoor) CVE-2014-6271 is a security bug in the broadly used Unix Bash shell. Bash is used to process certain commands across many internet daemons. It is a program that is used by various Unix-based systems to execute command scripts and command lines. Often it is installed as the system’s default command line interface.

Notes:

  • Environment variables (each running program having its own list of name/value pairs) occur in Unix-based and other operating systems that Bash supports. When one program is started by an earlier program, an initial list of environment variables is provided by the earlier program to the new program. Apart from this, named scripts (internal list of functions) are also maintained by Bash that can be executed from within.
  • By creating vulnerable versions of Bash, an attacker can gain unauthorized access to a computer system. By executing Bash with a chosen value in its environment variable list, vulnerable versions of Bash can be caused, that may allow remote code execution.
  • Scrutiny of the Bash source code history, reveal that concealed vulnerabilities have been present since approximately version 1.13 (1992). Lack of comprehensive change logs do not allow, the maintainers of Bash source code, to pinpoint the exact time of introduction of the vulnerability.


We don’t need no stinkin Collectors

#36 on the American Film Institute list of Top Movie Quotes is “Badges? We don’t need no stinkin badges” which has been used often (e.g., Blazing Saddles). The equivalent of this in the log management universe is a “Collector”. We are often asked how many “Collectors” we have readily available or how long it takes to develop a Collector.

These questions stem from a model used by programs such as ArcSight which depend on Early Binding. In an earlier era of computing, Early Binding was needed for the compiler could not create an entry in the virtual method table for the procedure being compiled. It has the advantage of being efficient, an important consideration when CPU and memory are in very short supply, like years ago.

Just in time languages such as .NET or Java adopt Late Binding where the v-table is computed at run time. Years ago, Late Binding had negative connotations in terms of performance but that hasn’t been true for at least 20 years now.

Early binding requires a fixed schema to be mandated for all possible entries and for input to be “normalized” to this schema. The benefit of the fixed plan is efficiency in output since the data is already normalized. While that may make some sense for compilers, input in formalized language grammars makes almost no sense in the log management universe, where the input is log data from sources that do not adopt any standardization at all. The downside of such an approach is to require a “Collector” to normalize a new log source to the normalized schema. Another consideration is that outputs can greatly vary depending onusage – there are many possible uses for the data, the limitation is only the users imagination. The Early Binding model however, is designed with fixed outputs in mind. These disadvantages limit such designs.

In contrast, EventTracker uses Late Binding, where the meaning of tokens can be assigned at output (run) time, rather than being fixed at receive time. Thus new log formats do not need a “Collector” to be available at ingest time. The desired output format can be specified at search or report time for easy viewing.This requires somewhat greater computing capacity with Moores Law to the rescue. Late Binding is the primary advantage of EventTrackers’ “Fast In, Smart Out” architecture.



Spray & Pray or 80/20

If you spend any time at all looking at log data from any server that is accessible to the Internet, you will be shocked at the brazen attempts to knock the castle over. They being within minutes of the server being available. They most commonly include port scans, login attempts using default username/password, web server attacks described by OWASP.

How can this possibly be? Given the sheer number of machines that are visible on the Internet? Don’t these guys have anything better to do?

The answer is automation and scripted attacks, also known as spray and pray. The bad guys are capitalists too (regardless of country of origin!) and need to maximize their effort, computing capacity and network bandwidth usage. Accordingly, they use automation to “knock on all available doors in a wealthy neighborhood” as efficiently and regularly as possible. Why pick on servers in developed countries? Because that’s where the payoff is likely to be higher. Its Risk v. Reward all the way.

The automated (first) wave of these attacks is to identify vulnerable machines and establish presence. Following waves may be staffed depending on the the location and identity and thus the potential value to be obtained by a greater investment of (scarce) expertise by the attacker.

Such attacks can be deterred quite simply by using secure (non-default) configuration, system patching and basic security defenses such as firewall and anti-virus. This explains the repeated exhortations of security pundits on “best practice” and also the rationale behind compliance standards and auditors trying to enforce basic minimum safeguards.

The 80/20 rule applies to attackers just as it does to defenders. Attackers are trying to cover 80% of the ground at 20% of the cost so as to at-least identify soft high value targets and at most steal from them. Defenders are trying to deter 80% of the attackers at 20% of cost by using basic best practices.

Guidance such as SANS Critical Controls or lessons from Verizon’s Annual Data Breach studies can help you prioritize your actions. Attackers depend on the fact that the majority of users do not follow basic security hygiene, don’t collect logs which would expose the attackers actions and certainly never actually look at the logs.

Defeating a “spray and pray” attacks requires basic tooling and discipline. The easy way to so this? We call it SIEM Simplified. Drop us a shout, it beats being a victim.



Hackers: What they are looking for and the abnormal activities you should be evaluating

Most hackers are looking into critical data for credential theft. A credential theft attack is when an attacker initially gains privileged access to a computer on a network and then uses freely available tooling to extract credentials from the sessions of other logged-on accounts. The most prevalent target for a credential theft is a “VIP account.” VIP account’s consist of contacts with highly sensitive data attached: access to accounts and secure data that many others within that organization probably don’t have.

It’s very important for administrators to be conscious of activities that increase the likelihood of a successful credential-theft attack.

These activities are:
• Logging on to unsecured computers with privileged accounts
• Browsing the Internet with a highly privileged account
• Configuring local privileged accounts with the same credentials across systems
• Overpopulation and overuse of privileged domain groups
• Insufficient management of the security of domain controllers.

There are specific accounts, servers, and infrastructure components that are the usual primary targets of attacks against Active Directory.

These accounts are:
• Permanently privileged accounts
• VIP accounts
• “Privilege-Attached” Active Directory accounts
• Domain controllers
• Other infrastructure services that affect identity, access, and configuration management, such as public key infrastructure (PKI) servers and systems management servers

Although pass-the-hash (PtH) and other credential theft attacks are ubiquitous today, it is because there is freely available tooling that makes it simple and easy to extract the credentials of other privileged accounts when an attacker has gained Administrator – or SYSTEM-level access to a computer.

Even without this tool, an attacker with privileged access to a computer can just as easily install keystroke loggers that capture keystrokes, screenshots, and clipboard contents. An attacker with privileged access to a computer can disable anti-malware software, install rootkits, modify protected files, or install malware on the computer that automates attacks or turns a server into a drive-by download host.

The tactics used to extend a breach beyond a single computer vary, but the key to propagating compromise is the acquisition of highly privileged access to additional systems. By reducing the number of accounts with privileged access to any system, you reduce the attack surface not only of that computer, but the likelihood of an attacker harvesting valuable credentials from the computer.



EventTracker’s SIEM Simplified team lead offers practical ways to analyze login and pre-authentication failures

Nikunj Shah, team lead of EventTracker SIEM Simplified team provides some practical tips on analyzing login and pre-authentication failures:

1) Learn and know how to identify login events and their descriptions. A great resource to find event IDs is here: http://technet.microsoft.com/en-us/library/cc787567(v=ws.10).aspx.

2) Identify and look into the event description. To analyze events efficiently and effectively you must analyze the event description. Within the login failure description, paying attention to the details like: failure reason, user name, logon type, workstation name and source network address are critical to your investigation and analysis. By identifying the description and knowing what to pay attention to, you will easily eliminate the noise.

When using a system like EventTracker, the display of the required fields used to showcase eliminates the noise and show you the immediate error results. EventTracker will provide a summary based on the total number of events for each failure type and user name to demonstrate the automation of your systems’ critical information.

Using IDS will help your enterprise run more efficiently and effectively with the analysis of traditional reports for the hundreds of events that happen every day. Doing this without the help of a management and a monitoring tool is nearly impossible.

Please reference here for detailed charts.



Simplify SIEM with services

To support security, compliance and operational requirements, specific and fast answers to the 4 W questions (Who, What, When, Where) are very desirable. These requirements drive the need to Security Information Event Management (SIEM) solutions that provide detailed and one-pain-of-glass visibility into this data, which is constantly generated within your information ecosystem. This visibility and the attendant effectiveness are made possibly by centralizing the collection, analysis and storage of log and other security data from sources throughout the enterprise network.

To obtain value from your SIEM solution, it must be watered and fed. This is an eternal commitment, whether your team chooses to do-it yourself or get someone to do it for you. This new white paper from EventTracker examines the pros and cons of using a specialist external service provider.

“Think about this for a second: a lot more people will engage professional services to help them RUN, not just DEPLOY, a SIEM. However, this is not the same as managed services, as those organization will continue to own their SIEM tools.” –Anton Chuvakin, Gartner Analyst



Known knowns, Unknown unknowns

“There are known knowns. These are things we know that we know. There are known unknowns. That is to say, there are things that we know we don’t know. But there are also unknown unknowns. There are things we don’t know we don’t know. ”
–Donald Rumsfeld, Secretary of Defense

In SIEM world, the known knowns are alerts. We configure rules to look at security data for threats/problems that we find to be interesting and bring them to the operators’ attention. This is a huge step up in the SIEM maturity scale from log ignorance. The Department of Homeland Security refers to this as ”If you see something, say something.” What do you do when you see something? You “do something,” better known as alert-driven workflow. In the early stages of a SIEM implementation there is a lot of time spent refining alert definitions in order to reduce “noise.”

While this approach addresses the “known knowns”, it does nothing for the “unknown unknowns”. To identify the unknown, you must stop waiting for alerts and instead search for the insights. This approach starts with a question rather than a reaction to an alert. Notice that often enough, it’s non IT persons asking the questions e.g., Who changed this file? Which systems did “Susan” access on Saturday?

This approach results in interactive investigation rather than the traditional drill down. For example:
- Show me all successful login’s over the weekend
- Filter these to show only those on server3
- Why did “Susan” login here? Show all “Susan” activity over the weekend…

This form of active data exploration requires a certain degree of expertise in log management tools, with experience and knowledge of the data set to review a thread that looks out of place. Once you get used to the idea, it is incredible to see how visible these patterns become to you. This is essential to “running a tight ship” and being aware of out of the ordinary patterns given the baseline. When staffing technical persons for the EventTracker SIEM Simplified service team, we are constantly looking for “insight hunters” instead of mere “alert responders.”  Alert responding is so 2013…



Top 5 bad assumptions about SIEM

The clichĂ© goes “When you assume, you make an ass out of u and me.” When implementing a SIEM solution, these five assumptions have the potential to get us in trouble. They stand in the way or organization and personal success and thus are best avoided.

5. Security by obscurity or my network is too unimportant to be attacked
Small businesses tend to be more innovative and cost-conscious. Is there such a thing as too small for hackers to care? In this blog post we outlined why this is almost never the case. As the Verizon Data Breach shows year in and year out, companies with 11-100 employees from 36 countries had the maximum number of breaches.

4. I’ve got to do it myself to get it right
Charles De Gaulle on humility “The graveyards are full of indispensable men”. Everyone tries to demonstrate multifaceted skill but its neither effective nor efficient. Corporations do it all the time. Tom Friedman explains it in “The World is Flat.”

3. Compliance = Security
This is only true if your auditor is your only threat actor. We tend to fear the known more than the unknown so it is often the case that we fear the (known) auditor more than we fear the (unknown) attacker. Among the myriad lessons from the Target breach, perhaps the most important is that “Compliance” does NOT equal Security.

2. All I have to do it plug it in, the rest happens by magic
Marketing departments of every security vendor would have you believe this of their magic appliance or software. When has this ever been true? Self-propelling lawn mower anyone?

1. It’s all about buying the most expen$ive technology
Kivas Fajo in “The Most Toys” the 70th episode of Star Trek TNG believed this. You could negotiate a 90% discount on a $200K solution and then park it as shelfware, what did you get? Wasted $20K is what. It’s always about using what you have.

Bad assumptions = bad decisions.
Always true.



Security is not something you buy, but something you do

The three sides of the security triangle are People, Processes and Technology.

SIEM-Triangles

  1. People –the key issues are: who owns the process, who is involved, what are their roles, are they committed to improving it and working together, and more importantly are they prepared to do the work to fix the problem?
  1. Process –can be defined as a trigger event which creates a chain of actions resulting in something being prepared for a customer of that process.
  1. Technology – Now that people are aligned, and the process developed and clarified, technology can be applied to ensure consistency in the process application and to provide the thin guiding rails to keep the process on track, making it easier to follow the process than not.

None of this is particularly new to CIOs and CSOs, yet how often have you seen six or seven digit “investments” sitting on datacenter racks, or even sometimes on actual storage shelves, unused or heavily underused? Organizations throw away massive amounts of money, then complain about “lack of security funds” and “being insecure.” Buying security technologies is far too often an easier task than utilizing them, and “operationalizing” them for many organizations. SIEM technology suffers from this problem as do many other “Monitoring” technologies.

Compliance and “checkbox mentality” makes this problem worse as people read the mandates and only pay attention to sections that refer to buying boxes.

Despite all this rhetoric, many managers equate information security with technology, completely ignoring the proper order. In reality, a skilled engineer with a so-so tool, but a good process is more valuable than an untrained person equipped with the best of tools.

As Gartner analyst Anton Chuvakin notes, “…if you got a $200,000 security appliance for $20,000 (i.e. at a steep 90% discount), but never used it, you didn’t save $180k – you only wasted $20,000!”

Security is not something you BUY, but something you DO.

 



IP Address is not a person

As we deal with forensic reviews of log data, our SIEM Simplified team is called upon to piece together a trail showing the four W’s: Who, What, When and Where. Logs can be your friend and if collected, centralized and indexed can get you answers very quickly.

There is a catch though. The “Where” question is usually answered by supplying either a system name or an IP Address which at the time in question was associated with that system name.

Is that good enough for the law? i.e., will the legal system accept that you are your IP Address?

Florida District Court Judge Ursula Ungaro says no.

Judge Ungaro was presented with a case brought by Malibu Media, who accused IP-address “174.61.81.171″ of sharing one of their films using BitTorrent without their permission. The Judge, however, was reluctant to issue a subpoena, and asked the company to explain how they could identify the actual infringer.

Responding to this order to show cause, Malibu Media gave an overview of their data gathering techniques. Among other things they explained that geo-location software was used to pinpoint the right location, and how they made sure that it was a residential address, and not a public hotspot.

Judge Ungaro welcomed the additional details, but saw nothing that actually proves that the account holder is the person who downloaded the file.

“Plaintiff has shown that the geolocation software can provide a location for an infringing IP address; however, Plaintiff has not shown how this geolocation software can establish the identity of the Defendant,” Ungaro wrote in an order last week.

“There is nothing that links the IP address location to the identity of the person actually downloading and viewing Plaintiff’s videos, and establishing whether that person lives in this district,” she adds.

As a side note, on April 26, 2012, Judge Ungaro ruled that an order issued by Florida Governor Rick Scott to randomly drug test 80,000 Florida state workers was unconstitutional. Ungaro found that Scott had not demonstrated that there was a compelling reason for the tests and that, as a result, they were an unreasonable search in violation of the Constitution.