Majority of Ransomware Attacks Last Year Exploited Old Bugs

Many vulnerabilities that ransomware operators used in 2022 attacks were years old and paved the way for the attackers to establish persistence and move laterally in order to execute their missions.

The vulnerabilities, in products from Microsoft, Oracle, VMware, F5, SonicWall, and several other vendors, present a clear and present danger to organizations that haven't remediated them yet, a report from Ivanti revealed last week.

Old Vulns Still Popular

Ivanti's report is based on an analysis of data from its own threat intelligence team and from those at Securin, Cyber Security Works, and Cyware. It offers an in-depth look at vulnerabilities that bad actors commonly exploited in ransomware attacks in 2022.

Ivanti's analysis showed that ransomware operators exploited a total of 344 unique vulnerabilities in attacks last year — an increase of 56 compared with 2021. Of this, a startling 76% of the flaws were from 2019 or before. The oldest vulnerabilities in the set were three remote code execution (RCE) bugs from 2012 in Oracle's products: CVE-2012-1710 in Oracle Fusion middleware and CVE-2012-1723 and CVE-2012-4681 in the Java Runtime Environment.

Srinivas Mukkamala, Ivanti's chief product officer, says that while the data shows ransomware operators weaponized new vulnerabilities faster than ever last year, many continued to rely on old vulnerabilities that remain unpatched on enterprise systems. 

"Older flaws being exploited is a byproduct of the complexity and time-consuming nature of patches," Mukkamala says. "This is why organizations need to take a risk-based vulnerability management approach to prioritize patches so that they can remediate vulnerabilities that pose the most risk to their organization."

The Biggest Threats

Among the vulnerabilities that Ivanti identified as presenting the greatest danger were 57 that the company described as offering threat actors capabilities for executing their entire mission. These were vulnerabilities that allow an attacker to gain initial access, achieve persistence, escalate privileges, evade defenses, access credentials, discover assets they might be looking for, move laterally, collect data, and execute the final mission.

The three Oracle bugs from 2012 were among 25 vulnerabilities in this category that were from 2019 or older. Exploits against three of them (CVE-2017-18362, CVE-2017-6884, and CVE-2020-36195) in products from ConnectWise, Zyxel, and QNAP, respectively, are not currently being detected by scanners, Ivanti said.

A plurality (11) of the vulnerabilities in the list that offered a complete exploit chain stemmed from improper input validation. Other common causes for vulnerabilities included path traversal issues, OS command injection, out-of-bounds write errors, and SQL injection. 

Widely Prevalent Flaws Are Most Popular

Ransomware actors also tended to prefer flaws that exist across multiple products. One of the most popular among them was CVE-2018-3639, a type of speculative side-channel vulnerability that Intel disclosed in 2018. The vulnerability exists in 345 products from 26 vendors, Mukkamala says. Other examples include CVE-2021-4428, the infamous Log4Shell flaw, which at least six ransomware groups are currently exploiting. The flaw is among those that Ivanti found trending among threat actors as recently as December 2022. It exists in at least 176 products from 21 vendors, including Oracle, Red Hat, Apache, Novell, and Amazon.

Two other vulnerabilities ransomware operators favored because of their widespread prevalence are CVE-2018-5391 in the Linux kernel and CVE-2020-1472, a critical elevation of privilege flaw in Microsoft Netlogon. At least nine ransomware gangs including those behind Babuk, CryptoMix, Conti, DarkSide, and Ryuk, have used the flaw, and it continues to trend in popularity among others as well, Ivanti said.

In total, the security found that some 118 vulnerabilities that were used in ransomware attacks last year were flaws that existed across multiple products.

"Threat actors are very interested in flaws that are present in most products," Mukkamala says.

None on the CISA List

Notably, 131 of the 344 flaws that ransomware attackers exploited last year are not included in the US Cybersecurity and Infrastructure Security Agency's closely followed Known Exploited Vulnerabilities (KEV) database. The database lists software flaws that threat actors are actively exploiting and which CISA assesses as being especially risky. CISA requires federal agencies to address vulnerabilities listed in the database on a priority basis and usually within two weeks or so.

"It's significant that these aren't in CISA's KEV because many organizations use the KEV to prioritize patches," Mukkamala says. That shows that while KEV is a solid resource, it doesn't provide a full view of all the vulnerabilities being used in ransomware attacks, he says.

Ivanti found that 57 vulnerabilities used in ransomware attacks last year by groups such as LockBit, Conti, and BlackCat, had low- and medium-severity scores in the national vulnerability database. The danger, according to the security vendor: This could lull organizations who use the score to prioritize patching into a false sense of security.