Security Experts:

Connect with us

Hi, what are you looking for?


Malware & Threats

Attacks Using Macro-Enabled Threats Jumped in December: Microsoft

Researchers at Microsoft are reporting a spike in the use of macros to spread malware via spam and social engineering.

Researchers at Microsoft are reporting a spike in the use of macros to spread malware via spam and social engineering.

The increase occurred during the past month. Last year, researchers at Sophos also detected an increase in macro-based malware.

“Using macros in Microsoft Office can help increase productivity by automating some processes,” according to the Microsoft Malware Protection Center. “However, malware authors have also exploited these capabilities. Since Microsoft set the default setting to “Disable all macros with notification”, the number of macro-related malware threat has declined. More recently we have seen new threats emerging that include some form of social engineering to convince users to manually enable macros and allow the malicious code to run.”

In particular, Microsoft has spotted two macro downloaders spreading through spam email campaigns: TrojanDownloader:W97M/Adnel and TrojanDownloader:O97M/Tarbir. The threats appear to be targeting Microsoft customers predominantly in the US and UK. 

According to Microsoft’s statistics, the number of Adnel and Tarbir encounters spiked in the middle of December. The spam emails are being spread using subject lines related to finances, such as ‘ACH Transaction Report’, ‘Invoice as requested’ and ‘Payment Details’.

“Similar to other malware that spreads through malicious binary email attachments (for example,TrojanDownloader:Win32/Upatre), macro malware serve as an infection gateway,” according to Microsoft. “Once the gate is opened, in this case by opening the email attachment with macros enabled, whatever is on the other side of the gate (the malware), will enter and infect the system.”

The email attachments continue with the financial theme with names such as ‘ACH Transfer 0084.doc.’

“These names are again designed to look like legitimate payment files and use social engineering to convince recipients to open them,” according to Microsoft. “Upon opening the Microsoft Office file (in this case a Word document), a user will be prompted to enable macros. By default, the macros in Microsoft Office are set as “Disable all macros with notification”. Until they are manually enabled, the malware code cannot run.”

Microsoft advises customers to be cautious of unsigned macros and macros from untrusted sources.

Written By

Click to comment

Expert Insights

Related Content

Malware & Threats

Microsoft plans to improve the protection of Office users by blocking XLL add-ins from the internet.


CISA, NSA, and MS-ISAC issued an alert on the malicious use of RMM software to steal money from bank accounts.


Chinese threat actor DragonSpark has been using the SparkRAT open source backdoor in attacks targeting East Asian organizations.


A recently disclosed vBulletin vulnerability, which had a zero-day status for roughly two days last week, was exploited in a hacker attack targeting the...


Russia-linked cyberespionage group APT29 has been observed using embassy-themed lures and the GraphicalNeutrino malware in recent attacks.

Application Security

Electric car maker Tesla is using the annual Pwn2Own hacker contest to incentivize security researchers to showcase complex exploit chains that can lead to...

Malware & Threats

Cybercrime in 2017 was a tumultuous year "full of twists and turns", with new (but old) infection methods, a major return to social engineering,...

Malware & Threats

Security researchers are warning of a new wave of malicious NPM and PyPI packages designed to steal user information and download additional payloads.