Threat Actors Discuss Leasing Zero-Day Exploits

Ransomware gangs can now afford to pay as much as $10m for zero-day exploits, but for those without the money, developers have discussed renting out malicious code, according to Digital Shadows.

The threat intelligence firm’s new report ⁠–⁠ Vulnerability Intelligence, Do You Know Where Your Flaws Are? ⁠–⁠ is based on a detailed analysis of the cybercrime underground.

It confirmed that ransomware actors are now wealthy enough to compete with state-backed operatives in buying zero-days.

“These prices can appear enormous but there‘s a key aspect to keep in mind. Whatever legitimate bug bounty programs offer — and we’ve often seen them offering multimillion-dollar bounties before ⁠–⁠ cyber-criminals must offer more in order to compete with them, given the risks (jail time) and additional requirements needed during illicit activity (i.e. money laundering),” the report claimed.

However, while there are easy pickings from exploiting exposed RDP appliances and phishing users, these actors are unlikely to spend big at present, it added.

For those without that kind of money, there’s another option ⁠–⁠ Digital Shadows also observed cyber-criminals discussing a potential “exploit-as-a-service” model.

“This model would allow capable threat actors to ‘lease’ zero-day exploits to other cyber-criminals to conduct cyber-attacks. In fact, while a developer can generate large profits when selling a zero-day exploit, it often takes them a significant amount of time to complete such a sale,” it explained.

“However, this model enables zero-day developers to generate substantial earnings by renting the zero-day out while waiting for a definitive buyer. Additionally, with this model, renting parties could test the proposed zero-day and later decide whether to purchase the exploit on an exclusive or non-exclusive basis.”

That said, legacy vulnerabilities still offer fertile hunting ground for most threat actors, who are even sharing databases of target organizations that have not patched specific systems such as Microsoft Exchange.

According to the report, the cybercrime community is adept at information sharing in this regard, with older members imparting wisdom to help novice threat actors.

“Besides sharing tutorials, experienced, trusted users often provide reviews of their preferred (or least favorite) tool on the market, just like any other good consumer would,” the report claimed.

“Reviews cover everything from vulnerability-scanning tools to online bulletproof-hosting services, and many include detailed descriptions of how they work. These diligent reviewers are helping their peers identify relevant products for exploitation and make more informed decisions.”

However, there’s no honor among thieves, with Digital Shadows also observing threat actors attempting to troll or scam fellow forum members.

By Phil Muncaster