When it comes to securing open source, visibility and transparency are vital writes Vivian Dufour, CEO of Meterian, and when a vulnerability is discovered, the ability to respond fast saves time, resource and reputations.

Recent high profile cyber security incidents have reinforced the importance of cleaning up the open-source software supply chain. From Heartbleed to the Apache Software Foundation’s Log4j vulnerability, these highly publicised incidents have exposed the threats associated with the software supply chain.

Open source security vulnerabilities are nothing new. Heartbleed was a security bug in the OpenSSL cryptography library that affected many systems. Similarly, Log4Shell is a severe vulnerability, however in the case of Log4j the number of affected systems could well run into potentially billions. Many cybersecurity experts have characterised Log4Shell as the single biggest, most critical vulnerability of the last decade.

These incidents have brought into sharp focus the risks and galvanised a range of responses at national and international level. It even prompted the White House to convene an Open Source Software Security Summit in January that was attended by leaders from global technology companies including Google, Meta, Apple, and Cisco. Members of the open source community were also represented at the summit, as well as US government agencies, including the Cybersecurity and Infrastructure Security Agency, the National Security Council and the National Institute of Standards and Technology.

The gathering may have been precipitated by the Log4Shell vulnerability, but the wider context was clear. How do we ensure source code, build, and distribution integrity to achieve effective open source security management?

Open source under the microscope

Technology companies have been using open source for years as it speeds up innovation and time to market. Indeed, most major software developments include open source software – including software used by the national security community.

Open source software brings unique value, but it also has unique security challenges. It is used extensively, however, the responsibility of ongoing security maintenance is carried out by a community of dedicated volunteers. These security incidents have demonstrated that the use of open source is so ubiquitous that no company can blindly continue in the mode of business as usual. Recent research showed that 73% of applications scanned have at least one vulnerability[i]. These can be buried deep in the open source software supply chain that software-driven businesses rely on for basic functionality and security to accelerate their time to market.

The known unknown

The concept of known knowns, known unknowns and unknown unknowns has been widely used as a risk assessment methodology. When it comes to cybersecurity and the voracity of threat actors to exploit vulnerabilities, it is a useful analogy.

Let’s take Apache Log4J as an example. Companies often create products by assembling open source and commercial software components. Almost all software will have some form of ability to journal activity and Log4j is a very common component used for this.

Java logger Log4j 2 – A zero-day vulnerability

Log4J was originally released in 2001, and over the last 20 years it has been used in billions of software developments and applications across the world. For logging incidents within software, Log4j is used by everything from the humble 404 error message, gaming software such as Minecraft, and Cloud providers such as iCloud and Amazon Web Services, as well as for all manner of software and security tools.[ii] On 9 December 2021, the zero-day vulnerability in the Java logger Log4j 2, known as Log4Shell, sent shockwaves across organisations as security teams scrambled to patch the flaw. If left unfixed, attackers can break into systems, steal passwords and logins, extract data, and infect networks with malicious software causing untold damage, not least to brand reputations.

However, herein lies the problem. How do you quickly patch what you don’t know you have?

Often in the race to innovate, the first thing sacrificed is up-to-date documentation. Without it how does a company know if Log4J is integrated within its application estate, let alone know if it has been previously patched.

Improving safety and trust when speed is of the essence

If we are to increase safety and trust in software, we must improve transparency and visibility across the entire software supply chain. Companies should have the ability to automatically identify open source components in order to monitor and manage security risk from publicly disclosed vulnerabilities. A software bill of materials (SBOM) should be a minimum for any project or development. Without such visibility of all component parts, security teams cannot manage risk and will be unaware, and potentially exposed, to dangers lurking in their software.

Case study – Full Visibility within an Hour

To give an example; one of the largest UK based financial services company with millions of customers across the world discovered it had Log4J embedded within dozens of in-house developed software projects. Having seen the first reports of the vulnerability at the start of the business day, within an hour the security team had identified projects using Log4j and were able to start work on follow up activities. By the end of the day, the entire business had a concise list of projects at risk, some of which were already remediated.

How was this achieved?

The company had automated tooling integrated into their software development environment with comprehensive component security. This enabled them to quickly identify those software projects which depended on the affected log4j component.

This visibility allowed the company to devise remediation plans to mitigate the risks of the vulnerability in Log4J. The company was able to target valuable resources across multiple locations to ensure fixes were applied quickly to critical business applications within just a couple of hours. While they were implementing an action plan based on the organisation’s use of Log4j, some of its competitors without such comprehensive tools were still in the information gathering stage.

Innovating securely

As organisations continue to innovate at pace in order to reduce time to market, the reliance on open source software continues to increase. However, when the security of a widely-used open source component or application is compromised, every company, every country, and every community is impacted.

The White House has taken an important first step in trying to identify the challenges present in the open source software supply chain and encourage the sharing of ideas on ways to mitigate risk and enhance resilience. Organisations can and should take advantage of the many benefits that open source software can deliver, but they must not do so blindly. Ensuring you know the exact make-up of your technology stack including all the component parts is an important first step. Choosing discovery tools that have the widest comprehensive coverage is important, and so too is the flexibility to grade alerts so that only the most pressing threats are highlighted. This avoids ‘alert fatigue’, and enables security teams to focus resource where it matters most, putting organisations in a good position to act fast when vulnerabilities are discovered.

Hackers faced with stronger security defences will continue to turn their attention to the weaker underbelly of the software supply chain. Now is the time for organisations to implement integrated and automated tooling to gain comprehensive risk control of components in their open-source software supply chain. Only by increasing visibility, coverage of known unknowns and transparency can companies stay one step ahead.