DIY SIP-based TDoS tool/number validity checker offered for sale


By Dancho Danchev

Over the past year, we observed an increase in publicly available managed TDoS (Telephony Denial of Service) services. We attribute this increase to the achieved ‘malicious economies of scale’ on behalf of the cybercriminals operating them, as well as the overall availability of proprietary/public DIY phone ring/SMS-based TDoS tools.

What are cybercriminals up to in terms of TDoS attack tools? Let’s take a peek inside a recently released DIY SIP-based (Session Initiation Protocol) flood tool, which also has the capacity to validate any given set of phone numbers.

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DIY Russian mobile number harvesting tool spotted in the wild


By Dancho Danchev

Earlier this year we profiled a newly released mobile/phone number harvesting application, a common tool in the arsenal of mobile spammers, as well as vendors of mobile spam services. Since the practice is an inseparable part of the mobile spamming process, cybercriminals continue periodically releasing new mobile number harvesting applications, update their features, but most interestingly, continue exclusively targeting Russian users.

In this post, I’ll profile yet another DIY mobile number harvesting tool available on the underground marketplace since 2011, and emphasize on its most recent (2013) updated feature, namely, the use of proxies.

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A peek inside a (cracked) commercially available RAT (Remote Access Tool)


By Dancho Danchev

In an attempt to add an additional layer of legitimacy to their malicious software, cybercriminals sometimes simply reposition them as Remote Access Tools, also known as R.A.Ts. What they seem to be forgetting is that, no legitimate Remote Access Tool would posses any spreading capabilities, plus, has the capacity to handle tens of thousands of hosts at the same time, or possesses built-in password stealing capabilities.

Pitched by its author as a Remote Access Tool, the DIY (do it yourself) malware that I’ll profile in this post is currently cracked, and available for both novice, and experienced cybercriminals to take advantage of at selected cybercrime-friendly communities.

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How mobile spammers verify the validity of harvested phone numbers – part two


By Dancho Danchev

Just as we anticipated earlier this year in our “How mobile spammers verify the validity of harvested phone number” post, mobile spammers and cybercriminals in general will continue ensuring that QA (Quality Assurance) is applied to their upcoming campaigns. This is done in an attempt to both successfully reach a wider audience and to charge a higher price for a verified database of mobile numbers.

In this post I’ll profile yet another commercially available phone/mobile number verification tool that’s exclusively supporting Huawei 3G USB modems.

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Cybercriminals offer spam-friendly SMTP servers for rent


By Dancho Danchev

In times when modern cybercriminals take advantage of the built-in SMTP engines in their malware platforms, as well as efficient and systematic abuse of Web-based email service providers for mass mailing fraudulent or malicious campaigns, others seem to be interested in the resurrection of an outdated, but still highly effective way to send spam, namely, through spam-friendly SMTP servers.

In this post, I’ll profile a recently posted underground market ad for spam-friendly SMTP servers, offered for sale for $30 on a monthly basis.

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American Airlines ‘You can download your ticket’ themed emails lead to malware


By Dancho Danchev

Cybercriminals are currently spamvertising tens of thousands of emails impersonating American Airlines in an attempt to trick its customers into thinking that they’ve received a download link for their E-ticket. Once they download and execute the malicious attachment, their PCs automatically join the botnet operated by the cybercriminal/gang of cybercriminals behind the campaign.

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A peek inside a ‘life cycle aware’ underground market ad for a private keylogger


By Dancho Danchev

What’s greed to some cybercriminals, is profit maximization to others, especially in times when we’re witnessing the maturing state of the modern cybercrime ’enterprise’. Many enter this vibrant marketplace as vendors without really realizing that, thanks to the increasing transparency within the cybercrime ecosystem, their basic and valued added services will be directly benchmarked against a competing vendor, sometime rendering their unique value proposition completely irrelevant. Others will take a different approach by releasing a ‘life cycle aware’ underground market ad and will still manage to generate some revenue, as well as secure a decent number of customers in the long-term.

In this post, I’ll profile a ‘life cycle aware’ underground market ad for a private keylogger, relying on a limited number of licenses for its business model.

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Spamvertised ‘Your order for helicopter for the weekend’ themed emails lead to malware


By Dancho Danchev

Cybercriminals are currently mass mailing tens of thousands of emails, in an attempt to trick users into thinking that the order for their “air transportation services has been accepted and processed”. In reality though, once users execute the malicious attachments, their PCs will automatically become part of the botnet managed by the malicious actors.

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DIY Skype ring flooder offered for sale


By Dancho Danchev

Thanks to the ease of generating a botnet, in 2013, stolen accounting data on a mass scale is a no longer a hot underground item, it’s a commodity, one that’s being offered by virtually all participants in the cybercrime ecosystem.

What happens once a Skype account gets compromised? There are several possible scenarios. The cybercriminals that (automatically) compromised it will either use the Skype credit for their own purposes, start spreading malware to the friends/colleagues of the compromised victim, or feed the accounting data into their arsenal of tools and tactics for launching TDoS (Telephony Denial of Service) services.

In this post, I’ll profile a novice cybercriminal’s underground market proposition, consisting of a DIY Skype ring flooder+training+a small amount of credit on a Skype account available in the package, and emphasize on why this particular release will never gain any market share, compared to the sophisticated and publicly available managed services.

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