Krebs on Security

Infrastructure Laundering: Blending in with the Cloud

In an effort to blend in and make their malicious traffic tougher to block, hosting firms catering to cybercriminals in China and Russia increasingly are funneling their operations through major U.S. cloud providers. Research published this week on one such outfit — a sprawling network tied to Chinese organized crime gangs and aptly named “Funnull” — highlights a persistent whac-a-mole problem facing cloud services.

In October 2024, the security firm Silent Push published a lengthy analysis of how Amazon AWS and Microsoft Azure were providing services to Funnull, a two-year-old Chinese content delivery network that hosts a wide variety of fake trading apps, pig butchering scams, gambling websites, and retail phishing pages.

Funnull made headlines last summer after it acquired the domain name polyfill[.]io, previously the home of a widely-used open source code library that allowed older browsers to handle advanced functions that weren’t natively supported. There were still tens of thousands of legitimate domains linking to the Polyfill domain at the time of its acquisition, and Funnull soon after conducted a supply-chain attack that redirected visitors to malicious sites.

Silent Push’s October 2024 report found a vast number of domains hosted via Funnull promoting gambling sites that bear the logo of the Suncity Group, a Chinese entity named in a 2024 UN report (PDF) for laundering millions of dollars for the North Korean Lazarus Group.

In 2023, Suncity’s CEO was sentenced to 18 years in prison on charges of fraud, illegal gambling, and “triad offenses,” i.e. working with Chinese transnational organized crime syndicates. Suncity is alleged to have built an underground banking system that laundered billions of dollars for criminals.

It is likely the gambling sites coming through Funnull are abusing top casino brands as part of their money laundering schemes. In reporting on Silent Push’s October report, TechCrunch obtained a comment from Bwin, one of the casinos being advertised en masse through Funnull, and Bwin said those websites did not belong to them.

Gambling is illegal in China except in Macau, a special administrative region of China. Silent Push researchers say Funnull may be helping online gamblers in China evade the Communist party’s “Great Firewall,” which blocks access to gambling destinations.

Silent Push’s Zach Edwards said that upon revisiting Funnull’s infrastructure again this month, they found dozens of the same Amazon and Microsoft cloud Internet addresses still forwarding Funnull traffic through a dizzying chain of auto-generated domain names before redirecting malicious or phishous websites.

Edwards said Funnull is a textbook example of an increasing trend Silent Push calls “infrastructure laundering,” wherein crooks selling cybercrime services will relay some or all of their malicious traffic through U.S. cloud providers.

“It’s crucial for global hosting companies based in the West to wake up to the fact that extremely low quality and suspicious web hosts based out of China are deliberately renting IP space from multiple companies and then mapping those IPs to their criminal client websites,” Edwards told KrebsOnSecurity. “We need these major hosts to create internal policies so that if they are renting IP space to one entity, who further rents it to host numerous criminal websites, all of those IPs should be reclaimed and the CDN who purchased them should be banned from future IP rentals or purchases.”

Reached for comment, Amazon referred this reporter to a statement Silent Push included in a report released today. Amazon said AWS was already aware of the Funnull addresses tracked by Silent Push, and that it had suspended all known accounts linked to the activity.

Amazon said that contrary to implications in the Silent Push report, it has every reason to aggressively police its network against this activity, noting the accounts tied to Funnull used “fraudulent methods to temporarily acquire infrastructure, for which it never pays. Thus, AWS incurs damages as a result of the abusive activity.”

“When AWS’s automated or manual systems detect potential abuse, or when we receive reports of potential abuse, we act quickly to investigate and take action to stop any prohibited activity,” Amazon’s statement continues. “In the event anyone suspects that AWS resources are being used for abusive activity, we encourage them to report it to AWS Trust & Safety using the report abuse form. In this case, the authors of the report never notified AWS of the findings of their research via our easy-to-find security and abuse reporting channels. Instead, AWS first learned of their research from a journalist to whom the researchers had provided a draft.”

Microsoft likewise said it takes such abuse seriously, and encouraged others to report suspicious activity found on its network.

“We are committed to protecting our customers against this kind of activity and actively enforce acceptable use policies when violations are detected,” Microsoft said in a written statement. “We encourage reporting suspicious activity to Microsoft so we can investigate and take appropriate actions.”

Richard Hummel is threat intelligence lead at NETSCOUT. Hummel said it used to be that “noisy” and frequently disruptive malicious traffic — such as automated application layer attacks, and “brute force” efforts to crack passwords or find vulnerabilities in websites — came mostly from botnets, or large collections of hacked devices.

But he said the vast majority of the infrastructure used to funnel this type of traffic is now proxied through major cloud providers, which can make it difficult for organizations to block at the network level.

“From a defenders point of view, you can’t wholesale block cloud providers, because a single IP can host thousands or tens of thousands of domains,” Hummel said.

In May 2024, KrebsOnSecurity published a deep dive on Stark Industries Solutions, an ISP that materialized at the start of Russia’s invasion of Ukraine and has been used as a global proxy network that conceals the true source of cyberattacks and disinformation campaigns against enemies of Russia. Experts said much of the malicious traffic  traversing Stark’s network (e.g. vulnerability scanning and password brute force attacks) was being bounced through U.S.-based cloud providers.

Stark’s network has been a favorite of the Russian hacktivist group called NoName057(16), which frequently launches huge distributed denial-of-service (DDoS) attacks against a variety of targets seen as opposed to Moscow. Hummel said NoName’s history suggests they are adept at cycling through new cloud provider accounts, making anti-abuse efforts into a game of whac-a-mole.

“It almost doesn’t matter if the cloud provider is on point and takes it down because the bad guys will just spin up a new one,” he said. “Even if they’re only able to use it for an hour, they’ve already done their damage. It’s a really difficult problem.”

Edwards said Amazon declined to specify whether the banned Funnull users were operating using compromised accounts or stolen payment card data, or something else.

“I’m surprised they wanted to lean into ‘We’ve caught this 1,200+ times and have taken these down!’ and yet didn’t connect that each of those IPs was mapped to [the same] Chinese CDN,” he said. “We’re just thankful Amazon confirmed that account mules are being used for this and it isn’t some front-door relationship. We haven’t heard the same thing from Microsoft but it’s very likely that the same thing is happening.”

Funnull wasn’t always a bulletproof hosting network for scam sites. Prior to 2022, the network was known as Anjie CDN, based in the Philippines. One of Anjie’s properties was a website called funnull[.]app. Loading that domain reveals a pop-up message by the original Anjie CDN owner, who said their operations had been seized by an entity known as Fangneng CDN and ACB Group, the parent company of Funnull.

“After I got into trouble, the company was managed by my family,” the message explains. “Because my family was isolated and helpless, they were persuaded by villains to sell the company. Recently, many companies have contacted my family and threatened them, believing that Fangneng CDN used penetration and mirroring technology through customer domain names to steal member information and financial transactions, and stole customer programs by renting and selling servers. This matter has nothing to do with me and my family. Please contact Fangneng CDN to resolve it.”

In January 2024, the U.S. Department of Commerce issued a proposed rule that would require cloud providers to create a “Customer Identification Program” that includes procedures to collect data sufficient to determine whether each potential customer is a foreign or U.S. person.

According to the law firm Crowell & Moring LLP, the Commerce rule also would require “infrastructure as a service” (IaaS) providers to report knowledge of any transactions with foreign persons that might allow the foreign entity to train a large AI model with potential capabilities that could be used in malicious cyber-enabled activity.

“The proposed rulemaking has garnered global attention, as its cross-border data collection requirements are unprecedented in the cloud computing space,” Crowell wrote. “To the extent the U.S. alone imposes these requirements, there is concern that U.S. IaaS providers could face a competitive disadvantage, as U.S. allies have not yet announced similar foreign customer identification requirements.”

It remains unclear if the new White House administration will push forward with the requirements. The Commerce action was mandated as part of an executive order President Trump issued a day before leaving office in January 2021.

Krebs on Security

MasterCard DNS Error Went Unnoticed for Years

The payment card giant MasterCard just fixed a glaring error in its domain name server settings that could have allowed anyone to intercept or divert Internet traffic for the company by registering an unused domain name. The misconfiguration persisted for nearly five years until a security researcher spent $300 to register the domain and prevent it from being grabbed by cybercriminals.

From June 30, 2020 until January 14, 2025, one of the core Internet servers that MasterCard uses to direct traffic for portions of the mastercard.com network was misnamed. MasterCard.com relies on five shared Domain Name System (DNS) servers at the Internet infrastructure provider Akamai [DNS acts as a kind of Internet phone book, by translating website names to numeric Internet addresses that are easier for computers to manage].

All of the Akamai DNS server names that MasterCard uses are supposed to end in “akam.net” but one of them was misconfigured to rely on the domain “akam.ne.”

This tiny but potentially critical typo was discovered recently by Philippe Caturegli, founder of the security consultancy Seralys. Caturegli said he guessed that nobody had yet registered the domain akam.ne, which is under the purview of the top-level domain authority for the West Africa nation of Niger.

Caturegli said it took $300 and nearly three months of waiting to secure the domain with the registry in Niger. After enabling a DNS server on akam.ne, he noticed hundreds of thousands of DNS requests hitting his server each day from locations around the globe. Apparently, MasterCard wasn’t the only organization that had fat-fingered a DNS entry to include “akam.ne,” but they were by far the largest.

Had he enabled an email server on his new domain akam.ne, Caturegli likely would have received wayward emails directed toward mastercard.com or other affected domains. If he’d abused his access, he probably could have obtained website encryption certificates (SSL/TLS certs) that were authorized to accept and relay web traffic for affected websites. He may even have been able to passively receive Microsoft Windows authentication credentials from employee computers at affected companies.

But the researcher said he didn’t attempt to do any of that. Instead, he alerted MasterCard that the domain was theirs if they wanted it, copying this author on his notifications. A few hours later, MasterCard acknowledged the mistake, but said there was never any real threat to the security of its operations.

“We have looked into the matter and there was not a risk to our systems,” a MasterCard spokesperson wrote. “This typo has now been corrected.”

Meanwhile, Caturegli received a request submitted through Bugcrowd, a program that offers financial rewards and recognition to security researchers who find flaws and work privately with the affected vendor to fix them. The message suggested his public disclosure of the MasterCard DNS error via a post on LinkedIn (after he’d secured the akam.ne domain) was not aligned with ethical security practices, and passed on a request from MasterCard to have the post removed.

Caturegli said while he does have an account on Bugcrowd, he has never submitted anything through the Bugcrowd program, and that he reported this issue directly to MasterCard.

“I did not disclose this issue through Bugcrowd,” Caturegli wrote in reply. “Before making any public disclosure, I ensured that the affected domain was registered to prevent exploitation, mitigating any risk to MasterCard or its customers. This action, which we took at our own expense, demonstrates our commitment to ethical security practices and responsible disclosure.”

Most organizations have at least two authoritative domain name servers, but some handle so many DNS requests that they need to spread the load over additional DNS server domains. In MasterCard’s case, that number is five, so it stands to reason that if an attacker managed to seize control over just one of those domains they would only be able to see about one-fifth of the overall DNS requests coming in.

But Caturegli said the reality is that many Internet users are relying at least to some degree on public traffic forwarders or DNS resolvers like Cloudflare and Google.

“So all we need is for one of these resolvers to query our name server and cache the result,” Caturegli said. By setting their DNS server records with a long TTL or “Time To Live” — a setting that can adjust the lifespan of data packets on a network — an attacker’s poisoned instructions for the target domain can be propagated by large cloud providers.

“With a long TTL, we may reroute a LOT more than just 1/5 of the traffic,” he said.

The researcher said he’d hoped that the credit card giant might thank him, or at least offer to cover the cost of buying the domain.

“We obviously disagree with this assessment,” Caturegli wrote in a follow-up post on LinkedIn regarding MasterCard’s public statement. “But we’ll let you judge— here are some of the DNS lookups we recorded before reporting the issue.”

As the screenshot above shows, the misconfigured DNS server Caturegli found involved the MasterCard subdomain az.mastercard.com. It is not clear exactly how this subdomain is used by MasterCard, however their naming conventions suggest the domains correspond to production servers at Microsoft’s Azure cloud service. Caturegli said the domains all resolve to Internet addresses at Microsoft.

“Don’t be like Mastercard,” Caturegli concluded in his LinkedIn post. “Don’t dismiss risk, and don’t let your marketing team handle security disclosures.”

One final note: The domain akam.ne has been registered previously — in December 2016 by someone using the email address um-i-delo@yandex.ru. The Russian search giant Yandex reports this user account belongs to an “Ivan I.” from Moscow. Passive DNS records from DomainTools.com show that between 2016 and 2018 the domain was connected to an Internet server in Germany, and that the domain was left to expire in 2018.

This is interesting given a comment on Caturegli’s LinkedIn post from an ex-Cloudflare employee who linked to a report he co-authored on a similar typo domain apparently registered in 2017 for organizations that may have mistyped their AWS DNS server as “awsdns-06.ne” instead of “awsdns-06.net.” DomainTools reports that this typo domain also was registered to a Yandex user (playlotto@yandex.ru), and was hosted at the same German ISP — Team Internet (AS61969).

Krebs on Security

Patch Tuesday, October 2024 Edition

Microsoft today released security updates to fix at least 117 security holes in Windows computers and other software, including two vulnerabilities that are already seeing active attacks. Also, Adobe plugged 52 security holes across a range of products, and Apple has addressed a bug in its new macOS 15 “Sequoia” update that broke many cybersecurity tools.

One of the zero-day flaws — CVE-2024-43573 — stems from a security weakness in MSHTML, the proprietary engine of Microsoft’s Internet Explorer web browser. If that sounds familiar it’s because this is the fourth MSHTML vulnerability found to be exploited in the wild so far in 2024.

Nikolas Cemerikic, a cybersecurity engineer at Immersive Labs, said the vulnerability allows an attacker to trick users into viewing malicious web content, which could appear legitimate thanks to the way Windows handles certain web elements.

“Once a user is deceived into interacting with this content (typically through phishing attacks), the attacker can potentially gain unauthorized access to sensitive information or manipulate web-based services,” he said.

Cemerikic noted that while Internet Explorer is being retired on many platforms, its underlying MSHTML technology remains active and vulnerable.

“This creates a risk for employees using these older systems as part of their everyday work, especially if they are accessing sensitive data or performing financial transactions online,” he said.

Probably the more serious zero-day this month is CVE-2024-43572, a code execution bug in the Microsoft Management Console, a component of Windows that gives system administrators a way to configure and monitor the system.

Satnam Narang, senior staff research engineer at Tenable, observed that the patch for CVE-2024-43572 arrived a few months after researchers at Elastic Security Labs disclosed an attack technique called GrimResource that leveraged an old cross-site scripting (XSS) vulnerability combined with a specially crafted Microsoft Saved Console (MSC) file to gain code execution privileges.

“Although Microsoft patched a different MMC vulnerability in September (CVE-2024-38259) that was neither exploited in the wild nor publicly disclosed,” Narang said. “Since the discovery of CVE-2024-43572, Microsoft now prevents untrusted MSC files from being opened on a system.”

Microsoft also patched Office, Azure, .NET, OpenSSH for Windows; Power BI; Windows Hyper-V; Windows Mobile Broadband, and Visual Studio. As usual, the SANS Internet Storm Center has a list of all Microsoft patches released today, indexed by severity and exploitability.

Late last month, Apple rolled out macOS 15, an operating system update called Sequoia that broke the functionality of security tools made by a number of vendors, including CrowdStrike, SentinelOne and Microsoft. On Oct. 7, Apple pushed an update to Sequoia users that addresses these compatibility issues.

Finally, Adobe has released security updates to plug a total of 52 vulnerabilities in a range of software, including Adobe Substance 3D Painter, Commerce, Dimension, Animate, Lightroom, InCopy, InDesign, Substance 3D Stager, and Adobe FrameMaker.

Please consider backing up important data before applying any updates. Zero-days aside, there’s generally little harm in waiting a few days to apply any pending patches, because not infrequently a security update introduces stability or compatibility issues. AskWoody.com usually has the skinny on any problematic patches.

And as always, if you run into any glitches after installing patches, leave a note in the comments; chances are someone else is stuck with the same issue and may have even found a solution.

Krebs on Security

April’s Patch Tuesday Brings Record Number of Fixes

If only Patch Tuesdays came around infrequently — like total solar eclipse rare — instead of just creeping up on us each month like The Man in the Moon. Although to be fair, it would be tough for Microsoft to eclipse the number of vulnerabilities fixed in this month’s patch batch — a record 147 flaws in Windows and related software.

Yes, you read that right. Microsoft today released updates to address 147 security holes in Windows, Office, Azure, .NET Framework, Visual Studio, SQL Server, DNS Server, Windows Defender, Bitlocker, and Windows Secure Boot.

“This is the largest release from Microsoft this year and the largest since at least 2017,” said Dustin Childs, from Trend Micro’s Zero Day Initiative (ZDI). “As far as I can tell, it’s the largest Patch Tuesday release from Microsoft of all time.”

Tempering the sheer volume of this month’s patches is the middling severity of many of the bugs. Only three of April’s vulnerabilities earned Microsoft’s most-dire “critical” rating, meaning they can be abused by malware or malcontents to take remote control over unpatched systems with no help from users.

Most of the flaws that Microsoft deems “more likely to be exploited” this month are marked as “important,” which usually involve bugs that require a bit more user interaction (social engineering) but which nevertheless can result in system security bypass, compromise, and the theft of critical assets.

Ben McCarthy, lead cyber security engineer at Immersive Labs called attention to CVE-2024-20670, an Outlook for Windows spoofing vulnerability described as being easy to exploit. It involves convincing a user to click on a malicious link in an email, which can then steal the user’s password hash and authenticate as the user in another Microsoft service.

Another interesting bug McCarthy pointed to is CVE-2024-29063, which involves hard-coded credentials in Azure’s search backend infrastructure that could be gleaned by taking advantage of Azure AI search.

“This along with many other AI attacks in recent news shows a potential new attack surface that we are just learning how to mitigate against,” McCarthy said. “Microsoft has updated their backend and notified any customers who have been affected by the credential leakage.”

CVE-2024-29988 is a weakness that allows attackers to bypass Windows SmartScreen, a technology Microsoft designed to provide additional protections for end users against phishing and malware attacks. Childs said one of ZDI’s researchers found this vulnerability being exploited in the wild, although Microsoft doesn’t currently list CVE-2024-29988 as being exploited.

“I would treat this as in the wild until Microsoft clarifies,” Childs said. “The bug itself acts much like CVE-2024-21412 – a [zero-day threat from February] that bypassed the Mark of the Web feature and allows malware to execute on a target system. Threat actors are sending exploits in a zipped file to evade EDR/NDR detection and then using this bug (and others) to bypass Mark of the Web.”

Update, 7:46 p.m. ET: A previous version of this story said there were no zero-day vulnerabilities fixed this month. BleepingComputer reports that Microsoft has since confirmed that there are actually two zero-days. One is the flaw Childs just mentioned (CVE-2024-21412), and the other is CVE-2024-26234, described as a “proxy driver spoofing” weakness.

Satnam Narang at Tenable notes that this month’s release includes fixes for two dozen flaws in Windows Secure Boot, the majority of which are considered “Exploitation Less Likely” according to Microsoft.

“However, the last time Microsoft patched a flaw in Windows Secure Boot in May 2023 had a notable impact as it was exploited in the wild and linked to the BlackLotus UEFI bootkit, which was sold on dark web forums for $5,000,” Narang said. “BlackLotus can bypass functionality called secure boot, which is designed to block malware from being able to load when booting up. While none of these Secure Boot vulnerabilities addressed this month were exploited in the wild, they serve as a reminder that flaws in Secure Boot persist, and we could see more malicious activity related to Secure Boot in the future.”

For links to individual security advisories indexed by severity, check out ZDI’s blog and the Patch Tuesday post from the SANS Internet Storm Center. Please consider backing up your data or your drive before updating, and drop a note in the comments here if you experience any issues applying these fixes.

Adobe today released nine patches tackling at least two dozen vulnerabilities in a range of software products, including Adobe After Effects, Photoshop, Commerce, InDesign, Experience Manager, Media Encoder, Bridge, Illustrator, and Adobe Animate.

KrebsOnSecurity needs to correct the record on a point mentioned at the end of March’s “Fat Patch Tuesday” post, which looked at new AI capabilities built into Adobe Acrobat that are turned on by default. Adobe has since clarified that its apps won’t use AI to auto-scan your documents, as the original language in its FAQ suggested.

“In practice, no document scanning or analysis occurs unless a user actively engages with the AI features by agreeing to the terms, opening a document, and selecting the AI Assistant or generative summary buttons for that specific document,” Adobe said earlier this month.

Krebs on Security

Patch Tuesday, March 2024 Edition

Apple and Microsoft recently released software updates to fix dozens of security holes in their operating systems. Microsoft today patched at least 60 vulnerabilities in its Windows OS. Meanwhile, Apple’s new macOS Sonoma addresses at least 68 security weaknesses, and its latest update for iOS fixes two zero-day flaws.

Last week, Apple pushed out an urgent software update to its flagship iOS platform, warning that there were at least two zero-day exploits for vulnerabilities being used in the wild (CVE-2024-23225 and CVE-2024-23296). The security updates are available in iOS 17.4, iPadOS 17.4, and iOS 16.7.6.

Apple’s macOS Sonoma 14.4 Security Update addresses dozens of security issues. Jason Kitka, chief information security officer at Automox, said the vulnerabilities patched in this update often stem from memory safety issues, a concern that has led to a broader industry conversation about the adoption of memory-safe programming languages [full disclosure: Automox is an advertiser on this site].

On Feb. 26, 2024, the Biden administration issued a report that calls for greater adoption of memory-safe programming languages. On Mar. 4, 2024, Google published Secure by Design, which lays out the company’s perspective on memory safety risks.

Mercifully, there do not appear to be any zero-day threats hounding Windows users this month (at least not yet). Satnam Narang, senior staff research engineer at Tenable, notes that of the 60 CVEs in this month’s Patch Tuesday release, only six are considered “more likely to be exploited” according to Microsoft.

Those more likely to be exploited bugs are mostly “elevation of privilege vulnerabilities” including CVE-2024-26182 (Windows Kernel), CVE-2024-26170 (Windows Composite Image File System (CimFS), CVE-2024-21437 (Windows Graphics Component), and CVE-2024-21433 (Windows Print Spooler).

Narang highlighted CVE-2024-21390 as a particularly interesting vulnerability in this month’s Patch Tuesday release, which is an elevation of privilege flaw in Microsoft Authenticator, the software giant’s app for multi-factor authentication. Narang said a prerequisite for an attacker to exploit this flaw is to already have a presence on the device either through malware or a malicious application.

“If a victim has closed and re-opened the Microsoft Authenticator app, an attacker could obtain multi-factor authentication codes and modify or delete accounts from the app,” Narang said. “Having access to a target device is bad enough as they can monitor keystrokes, steal data and redirect users to phishing websites, but if the goal is to remain stealth, they could maintain this access and steal multi-factor authentication codes in order to login to sensitive accounts, steal data or hijack the accounts altogether by changing passwords and replacing the multi-factor authentication device, effectively locking the user out of their accounts.”

CVE-2024-21334 earned a CVSS (danger) score of 9.8 (10 is the worst), and it concerns a weakness in Open Management Infrastructure (OMI), a Linux-based cloud infrastructure in Microsoft Azure. Microsoft says attackers could connect to OMI instances over the Internet without authentication, and then send specially crafted data packets to gain remote code execution on the host device.

CVE-2024-21435 is a CVSS 8.8 vulnerability in Windows OLE, which acts as a kind of backbone for a great deal of communication between applications that people use every day on Windows, said Ben McCarthy, lead cybersecurity engineer at Immersive Labs.

“With this vulnerability, there is an exploit that allows remote code execution, the attacker needs to trick a user into opening a document, this document will exploit the OLE engine to download a malicious DLL to gain code execution on the system,” Breen explained. “The attack complexity has been described as low meaning there is less of a barrier to entry for attackers.”

A full list of the vulnerabilities addressed by Microsoft this month is available at the SANS Internet Storm Center, which breaks down the updates by severity and urgency.

Finally, Adobe today issued security updates that fix dozens of security holes in a wide range of products, including Adobe Experience Manager, Adobe Premiere Pro, ColdFusion 2023 and 2021, Adobe Bridge, Lightroom, and Adobe Animate. Adobe said it is not aware of active exploitation against any of the flaws.

By the way, Adobe recently enrolled all of its Acrobat users into a “new generative AI feature” that scans the contents of your PDFs so that its new “AI Assistant” can  “understand your questions and provide responses based on the content of your PDF file.” Adobe provides instructions on how to disable the AI features and opt out here.