According to Symantec, it has seen large volumes of unsolicited emails hitting email inboxes, especially with many stores offering deals - via email - to tempt shoppers out over the US bank holiday weekend.
Replica watches, says the firm, are always a popular spam theme during holidays and the `Fourth' is no exception, with spam originating from a cluster of Brazilian IP addresses being involved with what looks to be a botnet-driven campaign.
According to the Softpedia newswire, meanwhile, another category of products advertised during the holidays are male enhancement pills.
These, says the East European ITsec newswire, are sold by rogue online pharmacies and carry serious health risks because they have not passed regulatory approval and might contain dangerous substances.
"Spam emails that are promoting popular gadgets and outdoor grilling products at a discounted rate are also being observed in yet another spam campaign", the newswire quotes the Symantec researchers as saying.
And since fireworks are closely associated with the Independence Day celebrations, the newswire adds that discounts for these types of items are also being advertised by spammers.
"Most of the domains used in else campaigns have been registered during the past week in preparation for the holiday", notes the newswire.
"Users are strongly advised against buying from spam sites. First of all, they expose themselves to financial fraud by handing over their credit card details to cyber crooks. Secondly, in case they are actually shipped, the products are of poor quality."