They sent it to your for a reason. I didn't get one, which tells me it's YOU specifically they are telling this to. More than likely, they ran a scan of all the sites on their servers that are running an outdated plugin that has a serious security hole, and they are doing you the favor (or are they twisting your arm, lol) of telling you to update it before wild Ukrainian Haxors start phishing for Craigslist accounts from a page they've created on your website that not even you can look at. Google will ban your site and block your IP, and Homeland Security will put you on the "no-fly" list because the illicit income being generated from your site is being used to fund radical turnip farmers outside Kiev, who want to resurrect the corpse of Lenin and reconstruct the old Soviet Union, for no other reason than to reduce the cost of vodka so that they can once again be able to afford two bottles a day, instead of just one. If you are going to be a turnip farmer, you should at least be able to walk around with a Kalashnikov muttering quotations from Marx and working your way through your second bottle of distilled potato juice.
And not only that, but your girlfriend will be overcome with the aroma of the Ukrainian Haxors pheromones and she will swoon into their arms and they shall whisk her away to some dank and moldy dungeon filled with all manner of steel torture devices and a locked room with nothing inside by a TV set that plays "Bridezilla" 24/7. (Most people choose the rack, with the heavy metal clamps they attach to your testicles, over the reality TV torture room.) And so naturally you will try to find her and help her to escape but it will be too late, she will turn on you, side with the Unkranian Haxors and their turnip farmer friends and force you to choose your method of torture while holding you at gunpoint (while your girlfriend stands around in a leather mini-skirt and halter-top and a leather quirt, just waiting for someone to tell her to use it on you. He black eyes are on fire with the delight of anticipating beating you, slowly.
So that's your choice. Update that buggy plugin and risk unknown software bugginess, or have to choose between screeching fat chicks in bridal dresses or having your scrotum stretched all the way to the floor. Or being brutally beaten by your now ex-girlfriend wildly swinging a long leather pole.