When a vulnerability isn’t closed for years — or why a vulnerability scanner is never enough

The number of vulnerabilities detected in code continues to rise. According to Kaspersky’s threat analysis, 5,200 critical vulnerabilities were found in the first half of this year alone — nearly 50% more than during the same period last year. At the same time, the average gap between the publication of information about a vulnerability and the first attempts to exploit it is shrinking. The rapid development of AI systems plays a significant role in this process: while helping companies find weaknesses in their code, AI simultaneously shows hackers how to exploit them quicker.

It would seem that solving the problem of security gaps is very easy. All you need do is set up a scanner, check the infrastructure more often, and update vulnerable systems. But statistics from the Kaspersky Incident Response service show the opposite: a significant number of cyberattacks begin precisely by exploiting a flaw — and these are often already known flaws, not zero-day vulnerabilities.

Using a scanner does not give you an effective vulnerability management process. A scanner merely finds flaws (not always promptly), and then the IT team is tasked with prioritizing and fixing them. These processes can drag on for weeks, and in the meantime an attacker can easily gain access to the given infrastructure.

Where time is lost

The first delay can occur immediately after information about a vulnerability appears in databases. In addition to monitoring for breaches, the information security team is normally handling a dozen-or-so other tasks, so it relies entirely on the scanner for monitoring. If the scanner is configured to run weekly, a new vulnerability will appear in the report in a few days. In a company where scans are conducted quarterly, this obviously happens much later. Attackers, on the other hand, actively monitor news feeds and learn about new vulnerabilities immediately.

When the report finally reaches the security team, it contains far more than just one issue, raising the question of where to start. Critical vulnerabilities are addressed first, but attackers might exploit more than just those. Meanwhile, prioritization decisions are rarely based on data: often, they’re based on the order of the errors in the report, the name of the vulnerable system (they start with the one everyone’s talking about), or increased activity from its owner. Because of this, the risk of overlooking a serious threat is very high. Finally, the IT department takes on the vulnerability, and… it ends up back in the queue: they need to check the update’s compatibility and wait for a maintenance window.

After installing the update, the specialists close the ticket with a clear conscience and mark the status as completed. But would anyone verify that the patch was applied to all affected machines? Even the one that was turned off at the time of installation? Probably not, and then the company would assume the vulnerability was fixed, even though it’ll actually remain in the infrastructure for an indefinite period. This is the worst possible outcome: the risk remains — yet it’s no longer visible.

Put it all together, and what we get is months passing between disclosure and actual resolution. There’s no one in particular to blame here: every participant in the chain did what they’re supposed to. It’s just that this chain itself is made up of links with gaps between them.

A recipe for vulnerability management

To give attackers as few opportunities to gain access to corporate infrastructure as possible, it’s important to ensure that an organization has four key processes clearly established:

1.       Inventory

It’s impossible to verify the security of a system that no one knows exists. At the same time, virtually any large infrastructure will contain things like having had a server set up “for a week” three years ago, a network device left over from previous business owners, or a workstation that was forgotten during an office move. And each of these assets can pose a serious threat.

The goal of inventory management is to ensure complete transparency of the IT infrastructure. To achieve this, an up-to-date list of assets is compiled.

2.       Prioritization

When analyzing vulnerabilities, a security specialist shouldn’t rely solely on ratings from public databases such as the NVD, for these don’t always rely the real severity of the actual potential damage caused by exploiting a vulnerability. The specific structure of an organization’s infrastructure will have a significant impact. For example, the same vulnerability in a server located in an isolated segment, and in a system accessible from the internet, represents two very different risks.

Effective prioritization takes into account not only the publicly reported severity level but also the role of the vulnerable asset within the infrastructure, the likelihood of exploitation, and actual attack trends.

3.       Configuration settings

Overly permissive access settings, disabled security mechanisms, and default accounts are not technically vulnerabilities, but they often serve as entry points for cybercriminals. To prevent an attacker from exploiting inadequate configuration settings, security teams should follow several basic security best practices:

• delete default accounts;
• use strong passwords and MFA;
• disable unused services;
• apply the principle of least privilege.

4.       Confirmation

Blind spots are particularly common at the last stage of the vulnerability management process. Typically, once the IT department formally installs an update, the vulnerability is considered patched. However, before breathing a final sigh of relief, it’s important to at least verify that the patch has been successfully applied to all affected systems and has actually resolved the vulnerability.

Five tasks — one solution

Our solution, the Kaspersky Vulnerability Management module for Kaspersky Next Optimum helps information security specialists establish centralized management of vulnerabilities, assets, and configuration errors. The product solves five key tasks:

• It reduces the time between publication of vulnerability data and its detection in assets. The product automatically inventories the infrastructure — tracking even long-forgotten assets — and continuously scans it for vulnerabilities. Scanning is performed in two ways: agent-based and agentless. In the former, the solution runs on top of Kaspersky Endpoint Security, which allows for in-depth analysis of workstations and servers without transmitting service credentials over the network. In the latter, it analyzes ports and services where no agent is present. Both methods complement each other, enabling complete coverage of the company’s infrastructure.
• Checks configurations. Compliance with security standards is verified using predefined profiles.
• Prioritizes vulnerabilities. Priorities are assigned based on severity level, the characteristics of the specific asset, likelihood of exploitation, and other parameters.
• Promptly fixes errors. This involves remediation recommendations and centralized patch management integrated into the familiar administration infrastructure.
• Helps ensure that the vulnerability is fully patched. A remediation task is considered complete only after a follow-up verification.

The Kaspersky Vulnerability Management Module helps transform vulnerability management from a series of disjointed actions into a well-thought-out cycle. Details about licensing can be found on the Kaspersky Next Optimum for small and mid-sized businesses offering page and more about Vulnerability Management Module — on the module’s home page.