Threat Intelligence Roundup: Five Lessons Learned Since Log4Shell

Editor’s Note: This blog was written by our teammates at Digital Shadows.

As the holiday season approaches, my family has a tradition of watching all of our favorite holiday movies—my favorite being Home Alone. It is the time for festive decorations, eggnog, and large heartwarming feasts with family and friends. Sadly, though, it is going to take a lot more than your aunt’s mystery casserole to ward off nefarious actors during the holiday season. After working in infosec for a few years, I am beginning to feel like Kevin McCallister spending every Christmas creatively warding off the Sticky Bandits.

In December 2020, as many people were busy Christmas shopping, there was the SolarWinds supply-chain attack that was a Russian advanced persistent threat (APT) group “APT29” (aka Nobelium). At least a hundred public and private organizations were impacted in this attack and the discovery and mitigation effort lasted well into the new year for many organizations.

On 24 November 2021, as Americans were preparing their stretchy Thanksgiving pants, a zero-day vulnerability impacting the widely used Apache Log4j Java library was discovered. The vulnerability was publicly disclosed on 09 December 2021. There are few CVE numbers that cybersecurity professionals can recite from memory, however, CVE-2021-44228 is likely one of them.

One year later, as we prepare for another holiday-season heist, Log4Shell remains a target for cybercriminals. Attackers have had a year to embed Log4Shell into their scripts, penetration-testing tools, and exploit kits. However, security teams have had a year to learn from the mistakes of others and are stronger for it.

Within this month’s vulnerability roundup, I am going to discuss five lessons learned since Log4Shell was announced on 09 December 2021.

1. Visibility Is Critical for Defense

There is an age-old saying in security that you can’t protect what you can’t see. Any time a high-profile vulnerability is disclosed, there are typically four types of reactions from IT teams:

  • Calm and collected as they are quickly able to identify or rule out potentially vulnerable assets
  • False sense of confidence, believing they are not impacted (only to find out they are)
  • Slow and steady wins the race, believe the vulnerability is over hyped and they have plenty of time before an exploit or proof of concept (PoC) is created
  • A mad panic and a scramble to remediate

Of course, of these scenarios, you’ll want your response to mirror option 1. Asset management is critical for organizations if they want to have a chance of defending against opportunistic attackers targeting zero-day vulnerabilities. True visibility, though, goes beyond knowing what your assets are; you’ll also want to know what business function they serve, where they are, and who can access them.

In addition to asset management, having sufficient logging capabilities is equally important to ensure all relevant events are being monitored. The 2022 Verizon Data Breach Investigation Report (DBIR) found that the average time to detect breaches is now a few days or less versus a month or more a few years ago. At first glance, it sounds like the security community is making great strides, but the report also revealed that the discovery method for over 50 percent of breaches was actor disclosure. This means organizations are more often than not detecting breaches because an attacker informed them via ransom note or a public announcement taking responsibility for the attack.

Responding to zero-day vulnerabilities includes searching through environments to ensure exploitation has not already occurred. Insufficient logging and monitoring capabilities would obstruct visibility and potentially result in a more significant breach.

2. Manage Risk with a Software Bill of Materials

A software bill of materials (SBOM) is a detailed inventory of all the ingredients that make up software components. Log4Shell demonstrated the importance of having a comprehensive understanding of tools and components used in enterprise environments.

Even when a software vendor identifies they use a particular piece of technology—such as the Apache Log4j Java library—it takes time to identify the full extent of how it is used and how quickly it can be mitigated. Particularly with open-source software, there is a large amount of creative freedom permitted to users in altering tooling to match their requirements. Having the visibility into which assets and business functions could be impacted is half the battle, allowing alternative mitigations, or workarounds, to be implemented.

3. Digital Risk Protection Can Reduce Complexity

The intelligence provided by ReliaQuest GreyMatter Digital Risk Protection (DRP) can help organizations make risk-informed decisions in a timely manner. No more scouring the web for information about vulnerabilities, such as if an exploit is available, or if the vulnerability has been embedded into penetration testing tools. GreyMatter DRP provides all of this context in one, centralized location: the ReliaQuest portal.

A vulnerability timeline for CVE-2021-4428

Vulnerability timeline for CVE-2021-44228 available on the ReliaQuest portal.

A large part of vulnerability and patch management is identifying the risk factors and the potential impact on business operations. Pivoting from vendor advisories, Twitter, blogs, GitHub, etc. To discover a more holistic view of a problem can add stress to an already difficult situation.

A table showing very high, high, and medium risk factors associated with CVE-2021-44228

Risk factors for CVE-2021-44228 available on the GreyMatter DRP platform.

Having a single source that captures all of these data sources reduces complexity. Is there evidence of widespread scanning to identify vulnerable devices? Are there any threat actors or groups already exploiting this vulnerability? ReliaQuest has a dedicated team of vulnerability intelligence analysts that combine automated collection with their own continuous monitoring and analysis in order to answer questions just like these.

4. Support Open-Source Projects in a Systematic Way

It was eye-opening to see how embedded Log4j was into so many commercial technologies. Similar to Apache, many open source projects allow organizations to use the software in commercial products free of charge. Open-source projects are often operated by volunteers with limited resources and no obligations to continue to develop projects. Organizations can be doing more to support these projects that are so critical to modern digital infrastructure and are not self-maintaining.

There are several ways to give back to open-source projects other than monetary support, including:

  • Hire open-source maintainers to work on open source
  • Develop an open-source award program or peer bonus fund
  • Start an open-source program office
  • Launch an open-source fund
  • Contribute a portion of your company equity to open source
  • Support and join open-source foundations
  • Fund and participate in open-source internships or retreats
  • Include open source in your corporate philanthropy initiatives

5. Manage Expectations from the Start

There have been quite a few vulnerabilities dubbed “4Shell” following Log4Shell, and I don’t know about you, but I am 4Shell-ed out. Enough4Shell. If this past year has taught me anything, though, it is that managing expectations is important. The full scope of the exposure or risk of vulnerabilities will not be clear right away. Things will change over time.

In intelligence, we rely on the facts and stray away from assumptions. It can be stressful not to have a full understanding of what is going on and how you are impacted. Focus on what is known and communicate it effectively to the proper stakeholders. More times than not, management just wants to know that you are aware of the situation and actively monitoring for updates.

Additionally, organizations should set clear expectations and procedures for employees to follow when responding to a critical vulnerability so there is less of a scramble. When stuff hits the fan, employees should have no doubts as to what needs to be done, who the stakeholders are, etc. This will lead to a more successful and less stressful vulnerability management response.

Conclusion

Despite the fact that the Grinch of cybercrime continues to rob IT professionals of a relaxing holiday season year after year, there is something working in our favor—experience. This year we are not only prepared, but expecting something to take place. Lean on your experience and take time to write down lessons learned after major events so you are not left pondering how you did it last time.