Google says spam emails not coming from Android botnets

The company on Thursday disputed security researchers from Microsoft and Sophos

Google on Thursday dismissed the possibility that a new wave of pharmacy, penny stock and e-card spam emails are being sent by Android spam botnets.

"Our analysis suggests that spammers are using infected computers and a fake mobile signature to try to bypass anti-spam mechanisms in the email platform they're using," a Google spokesman said via email in response to security researchers from Microsoft and antivirus firm Sophos who first identified what they believed to be the handiwork of an Android botnet.

Terry Zink, program manager for Microsoft Forefront Online Security, was the first to report about the spam messages in a blog post on Tuesday, noting that all of the emails come from Yahoo's servers and they are sent from Android devices. "We've all heard the rumors, but this is the first time I have seen it -- a spammer has control of a botnet that lives on Android devices," Zink said. "These devices login to the user's Yahoo Mail account and send spam."

In a new blog post Thursday, Zink said that it is entirely possible that the Android Message-IDs from the spam email headers and the "Sent from Yahoo! Mail on Android" taglines were added by Windows malware as part of an elaborate deception to make it appear that the spam was coming from Android devices. However, it's similarly possible that these messages appear in this way because they do in fact come from Android devices, he said.

"Before writing my previous post, I considered both options but selected the latter," he wrote.

Security researchers from Sophos have also analyzed the spam messages, which advertise generic meds, penny stocks and e-cards, and have arrived at the same conclusion. "The messages appear to originate from compromised Google Android smartphones or tablets," Sophos senior security advisor Chester Wisniewski said in a blog post on Thursday.

The researchers don't have a copy of the Android malware responsible for this spam campaign, but there is indirect evidence that suggests that the emails are being sent from Android devices.

The value of the Message-ID field in the email headers mentions "androidMobile" and the messages themselves end with "sent from Yahoo! Mail on Android," Zink said.

In addition, many of the originating IP addresses, which are present in the email headers, are assigned to mobile-phone network operators, Wisniewski said via email.

Based on the IP addresses seen so far, the infected devices are located in countries like Ukraine, Russia, Chile, Argentina, Venezuela, Indonesia, Thailand, Philippines, Lebanon, Oman and Saudi Arabia.

It's not clear how these devices got infected, but the likely scenario is that their owners downloaded pirated copies of legitimate commercial apps and those copies also contained malware, Wisniewski said.

The immediate consequence for victims could be a higher mobile phone bill. Sending thousands of spam messages can generate a lot of mobile data traffic and mobile data is not cheap in most countries.

Android Trojan apps have been used in the past to steal data, send SMS messages to premium-rate numbers or display unwanted advertisements. However, they've never been used to send spam before.

"If confirmed, the discovery of an Android botnet capable of sending spam will mark a milestone: at the moment there are more than one billion smartphones activated in the world and most of them are always connected to the Internet at all times, so they can pump up spam 24/7," said Bogdan Botezatu, a senior e-threat analyst at antivirus vendor BitDefender, via email.

BitDefender researchers are analyzing a malware sample that they believe might be connected to these spam campaigns. However, the company can't confirm the botnet's existence for now, Botezatu said.

Not all security researchers are convinced by the evidence found so far. "Currently we can't confirm - or deny - the existence of this supposed Android botnet," said Denis Maslennikov, a senior malware analyst at security firm Kaspersky Lab, via email. "The evidence put forward to claim that this is an Android botnet is based on data which is easily spoofed/forged."

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Lucian Constantin

IDG News Service
Show Comments

Cool Tech

Toys for Boys

Family Friendly

Stocking Stuffer

SmartLens - Clip on Phone Camera Lens Set of 3

Learn more >

Christmas Gift Guide

Click for more ›

Brand Post

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Aysha Strobbe

Microsoft Office 365/HP Spectre x360

Microsoft Office continues to make a student’s life that little bit easier by offering reliable, easy to use, time-saving functionality, while continuing to develop new features that further enhance what is already a formidable collection of applications

Michael Hargreaves

Microsoft Office 365/Dell XPS 15 2-in-1

I’d recommend a Dell XPS 15 2-in-1 and the new Windows 10 to anyone who needs to get serious work done (before you kick back on your couch with your favourite Netflix show.)

Maryellen Rose George

Brother PT-P750W

It’s useful for office tasks as well as pragmatic labelling of equipment and storage – just don’t get too excited and label everything in sight!

Cathy Giles

Brother MFC-L8900CDW

The Brother MFC-L8900CDW is an absolute stand out. I struggle to fault it.

Luke Hill

MSI GT75 TITAN

I need power and lots of it. As a Front End Web developer anything less just won’t cut it which is why the MSI GT75 is an outstanding laptop for me. It’s a sleek and futuristic looking, high quality, beast that has a touch of sci-fi flare about it.

Emily Tyson

MSI GE63 Raider

If you’re looking to invest in your next work horse laptop for work or home use, you can’t go wrong with the MSI GE63.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?