Even A False Positive Can Be Valuable

The financial services industry has come a long way in bolstering cyber resiliency and threat defenses, even as criminals have become more sophisticated at weakening infrastructures. Undoubtedly, the industry's success has been achieved through technological advancements, but more recently sharing information across organizations and borders has bolstered defenses. Still, more needs to be done to ensure the financial services industry can combat cyberthreats in a timely, cost-effective way.

The ability to utilize accurate cyberthreat intelligence (CTI) information across organizations is key to fighting cybercriminals. If we can't do this, it will take too long between when threats are discovered and when they're mitigated. Furthermore, while threat information may describe intrusions that were recently identified within a firm, similar incidents could have been taking place across the financial services industry for a longer time. We must work together to improve our collective ability to discover breaches and shorten the time it takes us to respond.

Understanding CTI Data
When a company initially receives CTI data, that firm is just a consumer of the information. In some cases, it might find that it has limited technical or operational capabilities to utilize some or all of the information effectively. For example, the firm may receive information about the use of malware hashes but not be able to scan for such files. The company then will realize that it needs to better understand what the data really means in order to use it effectively.

Understanding how to use CTI information, especially when the intrusion took place weeks or months earlier, is also important. If the firm looks for activity from the moment the CTI data is received, it could miss how the intrusion happened hundreds of days earlier. As a company becomes more experienced with cybersecurity, it also moves from primarily using the telemetry in the CTI data to leverage insights and contextual information and instead begins to anticipate hazards down the road, such as adversaries' motivations, tactics, techniques, and methodologies.

As a company learns to use shared CTI data, it starts to realize that some CTI data lacks sufficient context and may indicate a false positive — that is, what appears to be a problem is completely innocuous. False positives are a problem not only because they waste manpower and time, but also because they distract companies from dealing with legitimate security issues.

As a result, it's critical that security specialists and information security officers understand that not everything detected is malicious and that there are ways to categorize incidents in order to identify false positives. These can include examining logs, looking at the URL or IP address of past attacks, and further investigating other user activities involved in the incident. But even if something is identified as a false positive, this information is still important to other firms operating within any cyberthreat intelligence-sharing network. If a company knows that something is a false positive, it doesn't need to spend valuable time and resources investigating the threat.  

A feedback loop is vital in information-sharing communities. If a company finds a false positive, it's important that it can communicate with the original producer of the CTI data so that it can provide an update and send that to other members of the community.

Standardized Formats
One important factor to consider when sharing CTI data inside a community is the format in which it is shared. Improving security through collaboration isn't a new concept, but it has typically been achieved through manual interactions. Today, data sharing is facilitated through the use of standard languages, including Structured Threat Information Expression (STIX), the structure of the message describing the threat, and Trusted Automated Exchange of Indicator Information (TAXII), the transport to send the STIX message. STIX and TAXII allow CTI data to be accessed in a standardized format. These open standards are essential for the interoperability and machine processing that are key to acting on information quickly.

CTI data-sharing systems leverage these open standards and provide information through information-sharing communities to those companies that haven't begun using STIX/TAXII. These common standards also allow those defending networks to use CTI data from community sources such as Information Sharing and Analysis Centers and governmental organizations and leverage that information in various commercial and open source security tools. Open standards also address the problems companies face when using multiple vendors, where the bundling of CTI data may only work with one vendor's tools. CTI-sharing systems allow for information from multiple sources to be used in multiple tools that detect or defend the network.

The security threat and intelligence landscape is evolving quickly because adversaries are growing more sophisticated and motivated. To stay ahead of attacks and mitigate the security threats they pose, the financial services industry needs to ensure that the CTI data it shares, whether a false positive or not, is done so in a timely and automated way. Only then can we be best equipped to achieve our collective goals of accelerating our response and improving our defenses. 

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