Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Vulnerabilities / Threats

EternalBlue Longevity Underscores Patching Problem

Three years after the Shadow Brokers published zero-day exploits stolen from the National Security Agency, the SMB compromise continues to be a popular Internet attack.

EternalBlue, the exploit publicly leaked three years ago next month, continues to threaten unpatched Windows servers connected to the Internet, with more than 100 different sources using it to attack systems on a daily basis, according to a new report by cybersecurity firm Rapid7.

Internet-connected servers vulnerable to EternalBlue have steeply declined since the WannaCry ransomware attack used the exploit to infect hundreds of thousands of systems in May 2017, destroying data and disrupted operations. Still, more than 600,000 servers continue to allow server message block (SMB) connections on the public Internet, according to Rapid7's Internet monitoring system. 

While some businesses need to keep the SMB port open to support critical legacy applications, for the most part companies are failing to detect and secure their attack surface, says Bob Rudis, chief data scientist for Rapid7

"At this point, it is a well-known, super-versatile piece of code that unfortunately still works way too well — maybe not on Internet-facing servers, but certainly once an attacker gets inside a network," he says.

While the number of unpatched servers has declined significantly, the attack is still finding success, he says. "Vulnerable systems are not in the millions but the sub-millions, but there are still enough hosts out there for bad actors to do what they need to do," he adds.

Rapid7 is not the only company to see EternalBlue as a continuing threat. Remote exploitation of the vulnerability continues to be the top network threat detected by McAfee today, said Steve Grobman, chief technology officer of the security firm, during his RSA Security Conference keynote.

The SMB vulnerability, designated MS17-010 by Microsoft and assigned three different CVEs, has joined other vulnerabilities, such as the remote procedure call (RPC) issue — MS08-067 — that allowed the Conficker worm to propagate. And the BlueKeep vulnerability in the remote desktop protocol (RDP), CVE-2019-0708, announced last June in the remote desktop protocol still affects 60% of servers, totaling hundreds of thousands of systems, Grobman said.

Patching for these significant issues remains a problem, he said.

"Significant populations of machines are still not patched," Grobman said. "We recognize the criticality of patching, but the data suggests we are collectively not moving fast enough to patch known vulnerabilities, including those that have significant impacts."

Three years ago this month, a group of hackers calling themselves the Shadow Brokers, a nom de guerre taken from the sci-fi video game "Mass Effect," released files leaked from the National Security Agency, the United States' intelligence service, that included a number of significant exploits. EternalBlue became popular because it is easy to exploit and reliable, says Rapid7's Rudis.

While most ISPs are blocking SMB on residential networks, the fact that more than 600,000 computers and servers continue to expose the service to the Internet is a danger, even if the service is patched, he says.

"We do know that there are, well, I wouldn't say legitimate, but there are people, organizations that are deliberately sticking SMB on the Internet," Rudis says. "They know that it is problematic, they know that they are going to have to keep reimaging their servers, and they lament the requirement to keep them out there, but they at least know enough that these things shouldn't be connected to anything real."

Overall, the danger posed by still-vulnerable SMB servers should not be discounted, as they remain a platform from which to launch attacks, says Adam Meyers, vice president of intelligence for cybersecurity services firm CrowdStrike. 

"It is hard to say what is an infected host, what is a research system — there is just so much bad stuff on the Internet continuously occurring," he says. "And that is just the annoyance-level activity, not even targeted attacks where someone is going after you."

In the end, companies should be re-evaluating whether difficult-to-protect protocols, such as SMB, are worth having exposed to the Internet. For Rapid7's Rudis, the answer is a firm "no."

"If you are running SMB on the Internet, it's either a honeypot or you're an idiot — it really comes down to those two things," Rudis says. "You can't secure it." 

Related Content:

Check out The Edge, Dark Reading's new section for features, threat data, and in-depth perspectives. Today's top story: "With New SOL4Ce Lab, Purdue U. and DoE Set Sights on National Security."


Veteran technology journalist of more than 20 years. Former research engineer. Written for more than two dozen publications, including CNET News.com, Dark Reading, MIT's Technology Review, Popular Science, and Wired News. Five awards for journalism, including Best Deadline ... View Full Bio

Recommended Reading:

Comment  | 
Print  | 
More Insights
Newest First  |  Oldest First  |  Threaded View
7 Old IT Things Every New InfoSec Pro Should Know
Joan Goodchild, Staff Editor,  4/20/2021
Cloud-Native Businesses Struggle With Security
Robert Lemos, Contributing Writer,  5/6/2021
Defending Against Web Scraping Attacks
Rob Simon, Principal Security Consultant at TrustedSec,  5/7/2021
Register for Dark Reading Newsletters
White Papers
Cartoon Contest
Write a Caption, Win an Amazon Gift Card! Click Here
Latest Comment: What Virtual Reality phishing attacks will look like in 2030.
Current Issue
2021 Top Enterprise IT Trends
We've identified the key trends that are poised to impact the IT landscape in 2021. Find out why they're important and how they will affect you today!
Flash Poll
How Enterprises are Developing Secure Applications
How Enterprises are Developing Secure Applications
Recent breaches of third-party apps are driving many organizations to think harder about the security of their off-the-shelf software as they continue to move left in secure software development practices.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
PUBLISHED: 2021-05-11
A cross-site request forgery (CSRF) vulnerability in Jenkins Xray - Test Management for Jira Plugin 2.4.0 and earlier allows attackers to connect to an attacker-specified URL using attacker-specified credentials IDs obtained through another method, capturing credentials stored in Jenkins.
PUBLISHED: 2021-05-11
Jenkins Xray - Test Management for Jira Plugin 2.4.0 and earlier does not perform a permission check in an HTTP endpoint, allowing with Overall/Read permission to enumerate credentials IDs of credentials stored in Jenkins.
PUBLISHED: 2021-05-11
Jenkins P4 Plugin 1.11.4 and earlier does not perform permission checks in multiple HTTP endpoints, allowing attackers with Overall/Read permission to connect to an attacker-specified Perforce server using attacker-specified username and password.
PUBLISHED: 2021-05-11
A cross-site request forgery (CSRF) vulnerability in Jenkins P4 Plugin 1.11.4 and earlier allows attackers to connect to an attacker-specified Perforce server using attacker-specified username and password.
PUBLISHED: 2021-05-11
Jenkins Xcode integration Plugin 2.0.14 and earlier does not configure its XML parser to prevent XML external entity (XXE) attacks.