DHS warns feds about electronic billing ploy

A phishing campaign targeting government employees includes malware disguised as an attached invoice.

Shutterstock image: phishing for information.

The Department of Homeland Security's cybersecurity team has warned employees of federal, state and local agencies that they have been targeted by a phishing campaign masked as an unpaid bill.

The warning is contained in a Traffic Light Protocol: Green notice to government employees issued by DHS' National Cybersecurity and Communications Integration Center. The notice states that the education and financial sectors, and international, state, local and tribal organizations have also been targeted. TLP messages are sent to peer and partner organizations in affected areas and are not disseminated publicly.

The Oct. 17 notice was posted on the Public Intelligence open-source website on Dec. 15.

The email message, with the subject line "UNPAID INVOIC," says the recipient has an unpaid bill. An attached invoice purports to show payment information, but if the PDF file is opened, embedded JavaScript redirects the victims to a malicious website where additional malware is installed.

According to the NCCIC notice, the PDF file has been seen with various numbers after the word "invoice," which is spelled correctly in some of the messages and incorrectly in others. Nevertheless, NCCIC said all the messages likely originate from a single campaign.

Center officials also said an analysis conducted on the malware showed that the products of only 29 of 54 security vendors can currently detect it and that the campaign could lead affected computers to become more susceptible to the Dyre or Dyreza banking malware. Similar to other types of banking malware, Dyreza exploits vulnerabilities to give malicious actors remote access to infected machines and intercept sensitive login information such as usernames and passwords.

Most of the major security vendors -- including F-Secure, AVG, Bitdefender, McAfee, Kaspersky Lab and Symantec -- can detect the Dyreza malware. However, the new "UNPAID INVOIC" campaign could be using a newer variant of that malware, officials said.