Cisco Security Intelligence Operations has detected significant activity related to spam e-mail messages that claim to contain tax refund information from the Internal Revenue Service (IRS) for the recipient. The text in the e-mail message attempts to convince the recipient to open the link to update information prior to receiving the refund. However, the link contains a malicious .exe file that, when executed, attempts to infect the system with malicious code.
E-mail messages that are related to this threat (RuleID4258) may contain the following file:
The IRSReport__fdp.exe file has a file size of 1,147,904 bytes. The MD5 checksum, which is a unique identifier of the executable, is the following string: 0x28B03D79A0A278A7CA313577A1F3C245
The following text is a sample of the e-mail message that is associated with this threat outbreak:
Subject: Re: Your Income Tax Refund
Internal Revenue Service United States Department of the Treasury
The Internal Revenue Service has recently dispatched Tax Refunds. In order to have your tax refund sent to you, you will be required to re-update your information with us. In order to update information, kindly click on the "Get My Refund" link stated below to continue:
Get My Refund
Tax Refunds Department,
INTERNAL REVENUE SERVICE,
UNITED STATES DEPARTMENT OF TREASURY.
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.
Cisco Security Intelligence Operations
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