The antivirus specialists at McAfee have warned of a Trojan that disguises itself as a Firefox extension. It is currently being openly disseminated through spam emails that purport to come from Wal-Mart. If the recipient opens the mail attachment while running a Windows operating system, the Trojan then installs itself as a Firefox extension, presenting itself as a legitimate existing extension called numberedlinks. It then begins intercepting passwords and credit card numbers entered into the browser, which it then sends to an external server. McAfee has dubbed the Trojan "FormSpy," although the company is still currently categorizing its distribution as low.
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