Spammers have been busy with holidays and tragedies to exploit. As might be expected, some of the highlights in spam so far this month were Fourth of July-themed campaigns and messages related to the death of Michael Jackson. While Independence Day-themed campaigns are no longer an issue, malicious messages related to Jackson's death have not stopped, according to the "State of Spam" report put out by Symantec on Thursday. In addition, a spam campaign masquerading as a Twitter "friend" invitation is making the rounds, and end-of-the-year holiday-themed campaigns are expected to start early this year, Symantec said.

“As the interest surrounding Michael Jackson's life and death continues, internet users should expect to continue to see threats that try to play upon the emotions and curiosity of the public around this event,” the report states.

Since Jackson's death on June 25, multiple spammers have launched malicious campaigns aiming to infect users with malware or obtain sensitive information about victims. The campaigns have alluring subject lines, some hinting at murder, others claiming he is still alive.

One campaign exploiting Jackson's death is propagating a worm disguised as a file supposedly containing photos and music of the late entertainer. The malicious file that downloads the worm if opened is called, “MichaelJacksonsongsandpictures.doc.exe,” and the subject line to this campaign is, “Remembering Michael Jackson,” Symantec said in its report. Other Jackson- related campaigns aim to trick users into visiting malicious URLs through fake YouTube notifications or phony news stories. 

A separate phishing campaign is targeting Jackson concert ticket holders. In the message, a spammer purports to be a concert ticket officer from London and requests users send a reply with their personal information to receive reimbursement for the ticket, the Symantec report said.

Dylan Morss, senior manager of anti-spam engineering at Symantec, told on Friday that right now, he's heard a lot of concern about phishing. This threat is on peoples' minds because it leads to an immediate invasion of privacy and for corporations, it can lead to brand damage, Morss said.

In its State of Phishing report, also released Thursday, Symantec reported that there was a 21 percent increase in phishing attacks this month.

Another big spam trend this month was Independence Day-themed messages, which claimed to direct users to videos of fireworks, but were actually propagating Waledac, a worm embedded into email attachments that  spreads using the infected computer's emailing networks, the Symantec report said. The holiday weekend came and went, so spam using this theme has died down, but Symantec warned that users now need to be cautious of end-of-the- year holiday-themed campaigns.

“Spam campaigns focused on the holiday season are expected to start even earlier this year due to the current economic climate,” the Symantec report said. “Users will see spammers following suit and unleashing their end-of-year holiday campaigns during the next quarter.”

Currently, users also should be aware of a spam campaign claiming to be an invite from a Twitter "friend" that is propagating a worm, the report said. Messages come with the subject: “Your friend invited you to Twitter,” and contains a malicious attachment that users are directed to open called “Invitation card.” But the attachment is actually a mass-mailing worm first identified in February, called “[email protected],” that harvests email addresses from the infected computer and spreads by copying itself to removable devices and shared folders, Symantec said.