Threat Outbreak Alert: Malicious Tax Return Notification Email Messages on March 12, 2014
IntelliShield: Threat Outbreak Alert
2011 July 06 14:36 GMT
2014 March 17 12:37 GMT
Cisco Security Intelligence Operations has detected significant activity on March 12, 2014.
Cisco Security Intelligence Operations has detected significant activity related to spam email messages that contain a tax return notification for the recipient. The text in the email message attempts to persuade the recipient to open the attachment to view details. However, the .zip attachment contains malicious .exe file, that when executed, attempts to infect the system with malicious code.
Email messages that are related to this threat (RuleID858KVR) may contain the following files:
The doc.exe file has a file size of 29,696 bytes. The MD5 checksum, which is a unique identifier of the executable, is the following string: 0xB70B79F904984165FB0E3E8AE6B6CF8B
The Tax Report.xls.exe file in the Tax Report.zip attachment has a file size of 80,384 bytes. The MD5 checksum is the following string: 0x6FE4D3639767FF5376EE62BEE3CA862D
The Your_2013_TaxReturnReport.exe file in the Your_2013_TaxReturnReport.zip attachment has a file size of 224,768 bytes. The MD5 checksum is the following string: 0x459910B4C3ECFF73C8505B1AB0ADC5EC
The following text is a sample of the e-mail message that is associated with this threat outbreak:
Subject: IRS notification letter
Department of Tresaury Internal Revenue Source
Important information about your tax return
Subject: Tax Agent Report - Delayed Tax Returns
Please do not respond to this email
Tax agent report for delayed tax returns over 30 days
Please find attached your weekly report for the period ending 10/01/2013
What you need to do
Refer to the initial notification email with attachment we sent you with instructions on how to interpret your tax agent report.
Deputy Commissioner of Taxation
Subject: 2013 Tax Return Report!
Your 2013 tax return is under investigation, attached is a copy of the report. Kindly download, read and get back to us as soon as possible
Internal Revenue Service
Cisco Security Intelligence Operations analysts examine real-world e-mail traffic data that is collected from over 100,000 contributing organizations worldwide. This data helps provide a range of information about and analysis of global e-mail security threats and trends. Cisco will continue to monitor this threat and automatically adapt IronPort systems to protect customers. This report will be updated if there are significant changes or if the risk to end users increases.
Cisco IronPort Virus Outbreak Filters protect customers during the critical period between the first exploit of a virus outbreak and the release of vendor antivirus signatures. E-mail that is managed by Cisco and end users who are protected by Cisco IronPort web security appliances will not be impacted by these attacks. Cisco IronPort appliances are automatically updated to prevent both spam e-mail and hostile web URLs from being passed to the end user.
The security vulnerability applies to the following combinations of products.
Threat Outbreak Alert
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