Prosecutors in Finland this week commenced their criminal trial against Julius Kivimäki, a 26-year-old Finnish man charged with extorting a once popular and now-bankrupt online psychotherapy practice and thousands of its patients. In a 2,200-page report, Finnish authorities laid out how they connected the extortion spree to Kivimäki, a notorious hacker who was convicted in 2015 of perpetrating tens of thousands of cybercrimes, including data breaches, payment fraud, operating a botnet and calling in bomb threats.
In November 2022, Kivimäki was charged with attempting to extort money from the Vastaamo Psychotherapy Center. In that breach, which occurred in October 2020, a hacker using the handle “Ransom Man” threatened to publish patient psychotherapy notes if Vastaamo did not pay a six-figure ransom demand.
Vastaamo refused, so Ransom Man shifted to extorting individual patients — sending them targeted emails threatening to publish their therapy notes unless paid a 500-euro ransom. When Ransom Man found little success extorting patients directly, they uploaded to the dark web a large compressed file containing all of the stolen Vastaamo patient records.
Security experts soon discovered Ransom Man had mistakenly included an entire copy of their home folder, where investigators found many clues pointing to Kivimäki’s involvement. By that time, Kivimäki was no longer in Finland, but the Finnish government nevertheless charged Kivimäki in absentia with the Vastaamo hack. The 2,200-page evidence document against Kivimäki suggests he enjoyed a lavish lifestyle while on the lam, frequenting luxury resorts and renting fabulously expensive cars and living quarters.
But in February 2023, Kivimäki was arrested in France after authorities there responded to a domestic disturbance call and found the defendant sleeping off a hangover on the couch of a woman he’d met the night before. The French police grew suspicious when the 6′ 3″ blonde, green-eyed man presented an ID that stated he was of Romanian nationality.
A redacted copy of an ID Kivimaki gave to French authorities claiming he was from Romania.
Finnish prosecutors showed that Kivimäki’s credit card had been used to pay for the virtual server that hosted the stolen Vastaamo patient notes. What’s more, the home folder included in the Vastaamo patient data archive also allowed investigators to peer into other cybercrime projects of the accused, including domains that Ransom Man had access to as well as a lengthy history of commands he’d executed on the rented virtual server.
Some of those domains allegedly administered by Kivimäki were set up to smear the reputations of different companies and individuals. One of those was a website that claimed to have been authored by a person who headed up IT infrastructure for a major bank in Norway which discussed the idea of legalizing child sexual abuse.
Another domain hosted a fake blog that besmirched the reputation of a Tulsa, Okla. man whose name was attached to blog posts about supporting the “white pride” movement and calling for a pardon of the Oklahoma City bomber Timothy McVeigh.
Kivimäki appears to have sought to sully the name of this reporter as well. The 2,200-page document shows that Kivimäki owned and operated the domain krebsonsecurity[.]org, which hosted various hacking tools that Kivimäki allegedly used, including programs for mass-scanning the Internet for systems vulnerable to known security flaws, as well as scripts for cracking database server usernames and passwords, and downloading databases.
Ransom Man inadvertently included a copy of his home directory in the leaked Vastaamo patient data. A lengthy history of the commands run by that user show they used krebsonsecurity-dot-org to host hacking and scanning tools.
Mikko Hyppönen, chief research officer at WithSecure (formerly F-Secure), said the Finnish authorities have done “amazing work,” and that “it’s rare to have this much evidence for a cybercrime case.”
Petteri Järvinen is a respected IT expert and author who has been following the trial, and he said the prosecution’s case so far has been strong.
“The National Bureau of Investigation has done a good job and Mr Kivimäki for his part some elementary mistakes,” Järvinen wrote on LinkedIn. “This sends an important message: online crime does not pay. Traces are left in the digital world too, even if it is very tedious for the police to collect them from servers all around the world.”
Antti Kurittu is an information security specialist and a former criminal investigator. In 2013, Kurittu worked on an investigation involving Kivimäki’s use of the Zbot botnet, among other activities Kivimäki engaged in as a member of the hacker group Hack the Planet (HTP). Kurittu said it remains to be seen if the prosecution can make their case, and if the defense has any answers to all of the evidence presented.
“Based on the public pretrial investigation report, it looks like the case has a lot of details that seem very improbable to be coincidental,” Kurittu told KrebsOnSecurity. “For example, a full copy of the Vastaamo patient database was found on a server that belonged to Scanifi, a company with no reasonable business that Kivimäki was affiliated with. The leaked home folder contents were also connected to Kivimäki and were found on servers that were under his control.”
The Finnish daily yle.fi reports that Kivimäki’s lawyers sought to have their client released from confinement for the remainder of his trial, noting that the defendant has already been detained for eight months.
The court denied that request, saying the defendant was still a flight risk. Kivimäki’s trial is expected to continue until February 2024, in part to accommodate testimony from a large number of victims. Prosecutors are seeking a seven-year sentence for Kivimäki.
Microsoft today released updates to fix more than five dozen security holes in its Windows operating systems and related software, including three “zero day” vulnerabilities that Microsoft warns are already being exploited in active attacks.
The zero-day threats targeting Microsoft this month include CVE-2023-36025, a weakness that allows malicious content to bypass the Windows SmartScreen Security feature. SmartScreen is a built-in Windows component that tries to detect and block malicious websites and files. Microsoft’s security advisory for this flaw says attackers could exploit it by getting a Windows user to click on a booby-trapped link to a shortcut file.
Kevin Breen, senior director of threat research at Immersive Labs, said emails with .url attachments or logs with processes spawning from .url files “should be a high priority for threat hunters given the active exploitation of this vulnerability in the wild.”
The second zero day this month is CVE-2023-36033, which is a vulnerability in the “DWM Core Library” in Microsoft Windows that was exploited in the wild as a zero day and publicly disclosed prior to patches being available. It affects Microsoft Windows 10 and later, as well as Microsoft Windows Server 2019 and subsequent versions.
“This vulnerability can be exploited locally, with low complexity and without needing high-level privileges or user interaction,” said Mike Walters, president and co-founder of the security firm Action1. “Attackers exploiting this flaw could gain SYSTEM privileges, making it an efficient method for escalating privileges, especially after initial access through methods like phishing.”
The final zero day in this month’s Patch Tuesday is a problem in the “Windows Cloud Files Mini Filter Driver” tracked as CVE-2023-36036 that affects Windows 10 and later, as well as Windows Server 2008 at later. Microsoft says it is relatively straightforward for attackers to exploit CVE-2023-36036 as a way to elevate their privileges on a compromised PC.
Beyond the zero day flaws, Breen said organizations running Microsoft Exchange Server should prioritize several new Exchange patches, including CVE-2023-36439, which is a bug that would allow attackers to install malicious software on an Exchange server. This weakness technically requires the attacker to be authenticated to the target’s local network, but Breen notes that a pair of phished Exchange credentials will provide that access nicely.
“This is typically achieved through social engineering attacks with spear phishing to gain initial access to a host before searching for other vulnerable internal targets – just because your Exchange Server doesn’t have internet-facing authentication doesn’t mean it’s protected,” Breen said.
Breen said this vulnerability goes hand in hand with three other Exchange bugs that Microsoft designated as “exploitation more likely:” CVE-2023-36050, CVE-2023-36039 and CVE-2023-36035.
Finally, the SANS Internet Storm Center points to two additional bugs patched by Microsoft this month that aren’t yet showing signs of active exploitation but that were made public prior to today and thus deserve prioritization. Those include: CVE-2023-36038, a denial of service vulnerability in ASP.NET Core, with a CVSS score of 8.2; and CVE-2023-36413: A Microsoft Office security feature bypass. Exploiting this vulnerability will bypass the protected mode when opening a file received via the web.
Windows users, please consider backing up your data and/or imaging your system before applying any updates. And feel free to sound off in the comments if you experience any difficulties as a result of these patches.