Separate of the patches it released, Microsoft on Tuesday warned of attacks underway that are targeting a zero-day vulnerability residing in XML Core Services, according to an advisory. The exploits are being launched against Internet Explorer users by tricking them, usually through a legitimate-looking email or instant messenger conversation, to visit a malicious website. Microsoft does not have a patch for the vulnerability, but as part of the advisory, it issued what Microsoft officials call "an effective workaround that stops would-be attackers from taking advantage of the issue via Internet Explorer."