HackerOne has fired one of its employees for collecting bug bounties from its customers after alerting them to vulnerabilities in their products — bugs that had been found by other researchers and disclosed privately to HackerOne via its coordinated vulnerability disclosure program.
HackerOne discovered the caper when one of its customers asked the organization to investigate a vulnerability disclosure that was made outside the HackerOne platform in June. The customer, like other clients of bug bounty programs, uses HackerOne to collect and report vulnerabilities in its products that independent security researchers might have discovered. In return, the company pays a reward — or bug bounty — for reported vulnerabilities.
In this instance, the HackerOne customer said an anonymous individual had contacted them about a vulnerability that was very similar to another bug in its technology that a researcher had previously submitted via the HackerOne platform.
Bug collisions — where two or more researchers might independently unearth the same vulnerability — are not uncommon. "However, this customer expressed skepticism that this was a genuine collision and provided detailed reasoning," HackerOne said in a report summarizing the incident. The customer described the individual — who used the handle "rzlr" — as using intimidating language in communicating information about the vulnerability, HackerOne said.
The company's investigation of the June 22, 2022, tip almost immediately pointed to multiple customers likely being contacted in the same manner. HackerOne researchers began probing every scenario where someone might have gained access to its vulnerability disclosure data: whether someone might have compromised one of its systems, gained remote access some other way, or if the disclosure had resulted from a misconfiguration. The data quickly pointed to the threat actor being an insider with access to the vulnerability data.
HackerOne's investigators then looked at their log data on employee access to vulnerability disclosures and found that just one employee had accessed each of the disclosures that customers reported as being suspicious. "Within 24 hours of the tip from our customer, we took steps to terminate that employee's system access and remotely locked their laptop pending further investigation," HackerOne said.
The company found the former employee had created a fictitious HackerOne account and collected bounties for a handful of disclosures. HackerOne worked with the relevant payment providers in each instance to confirm the bounties were paid into a bank account connected with the now-former employee. By analyzing the individual's network traffic, the investigators were also able to link the fictitious account to the ex-employee's primary HackerOne account.
Mike Parkin, senior technical engineer at Vulcan Cyber, says incidents like this can undermine the trust that is key to the success of crowdsourced vulnerability disclosure programs such as the one that HackerOne manages. "Trust is a big factor in vulnerability research and can play a large part in many bug bounty programs," Parkin says. "So, when someone effectively steals another researcher's work and presents it as their own, that foundational trust can be stretched."
Parkin praised HackerOne for being transparent and acting quickly to address the situation. "Hopefully this incident won't affect the vulnerability research ecosystem overall, but it may lead to deeper reviews of bug bounty submissions going forward," he says.
HackerOne said the former employee — who started only on April 4 — directly communicated with a total of seven of its customers. It urged any other customers that might have been contacted by an individual using the handle rzlr to contact the company immediately, especially if the communication had been aggressive or threatening in tone.
The company also reassured hackers who have signed up for the platform that their eligibility for any bounties they might receive for vulnerability disclosures had not been adversely impacted. "All disclosures made from the threat actor were considered duplicates. Bounties applied to these submissions did not impact the original submissions."
HackerOne said it would contact hackers whose reports the ex-employee might have accessed and attempted to resubmit. "Since the founding of HackerOne, we have honored our steadfast commitment to disclosing security incidents because we believe that sharing security information is essential to building a safer Internet," the company said.
Following the incident, HackerOne has identified several areas where it plans to bolster controls. These include improvements to its logging capabilities, adding employees to monitor for insider threats, enhancing its employee screening practices during the hiring process, and controls for isolating data to limit damage from incidents of this type.
Jonathan Knudsen, head of global research at Synopsys Cybersecurity Research Center, says HackerOne's decision to communicate clearly about the incident and its response to it is an example of how organizations can limit damage. "Security incidents are often viewed as embarrassing and irredeemable," he says.
But being completely transparent about what happened can increase credibility and garner respect from customers. "HackerOne has taken an insider threat incident and responded in a way that reassures customers that they take security very seriously, are capable of responding quickly and effectively, and are continuously examining and improving their processes," Knudsen says.