Tag Archives: Spamming

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

Posted on by

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.

More details: Continue reading →

Cybercriminals offer spam-friendly SMTP servers for rent

Posted on by

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providers for mass mailing fraudulent or malicious campaigns, others seem to be interested in the resurrection of an outdated, but still highly effective way to send spam, namely, through spam-friendly SMTP servers.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.

More details: Continue reading →

Segmented Russian “spam leads” offered for sale

Posted on by

By Dancho Danchev

What is the Russian underground up to when it comes to ‘spear phishing’ attacks? How prevalent is the tactic among Russian cybercriminals? What “data acquisition tactics” do they rely on, and just how sophisticated are their “data mining” capabilities?

Let’s find out by emphasizing on a recent underground market advertisement offering access to data which can greatly improve the click-through rate for a spear phishing campaign. The irony? It’s being pitched as “spam leads”.

More details:

Continue reading →

Cybercriminals release automatic CAPTCHA-solving bogus Youtube account generating tool

Posted on by

By Dancho Danchev

For years, thanks to the currently mature human-driven ecosystem offering CAPTCHA-solving as a service, cybercriminals have been persistently and automatically abusing major Web properties by undermining the “chain of trust” that these properties rely on so extensively.

Still living in a world supposedly dominated by malware-infected bots, this myopia has resulted in the rise of these managed services, rendering any recent CAPTCHA “innovations” useless since they continue relying on humans – the very species that CAPTCHA is supposed to be recognizable by in the first place.

Just how easy is it to automatically register tens of thousands of bogus accounts at, let’s say, YouTube? In this post I’ll profile a recently released tool that’s relying on API keys offered by a CAPTCHA-solving services, automating the account registration process in combination with the use of malware-infected hosts as proxies.

More details:

Continue reading →

Russian spammers release Skype spamming tool

Posted on by

By Dancho Danchev

Taking advantage of DIY spamming tools and harvested databases of user names, cybercriminals have been systematically abusing multiple instant messaging services in an attempt to trick as many users as possible into interacting with their malicious campaign.

In this post, I’ll profile a newly released DIY Skype spamming tool, discuss its main features, and whether or not it can lead to an increase in the overall spam levels affecting Microsoft’s Skype.

More details:

Continue reading →

Spamvertised ‘Download your USPS Label’ themed emails serve malware

Posted on by

By Dancho Danchev

Cybercriminals are currently spamvertising millions of emails impersonating the United States Postal Service (USPS), in an attempt to trick end and corporate users into downloading and unpacking the malicious .zip attachment distributed by them.

What’s so special about this campaign? Where is the malicious sample phoning back to? Are there more malware samples that also phoned back to the same command control servers in the past? Let’s find out.

More details:

Continue reading →

Russian Ask.fm spamming tool spotted in the wild

Posted on by

By Dancho Danchev

On their way to occupy an even bigger market share, spammers constantly look for new ways to increase visitor conversion, and target as many users as possible with the least amount of time and money invested.

For years, their tactics included the development of cybercrime friendly online communities, sophisticated harvesting and validation of emails and user names across popular Web services, abusing the Domain Keys Identified Mail (DKIM) trust established between the most popular providers of free Web based email, development of DIY image spam generating platforms, conversion of malware-infected hosts into spam spewing zombies, and most importantly, efficient ways to bypass anti-spam filters put in place by the security industry.

In this post, I’ll profile a recently advertised Ask.fm spamming tool, capable of spamming thousands of users through the use of proxies, which are in fact malware-infected hosts converted to anonymization proxies.

More details:

Continue reading →