Exploits are released based on a recent TIFF image-rendering flaw.
While Microsoft has yet to issue a permanent patch for a known exploit, the code could become widely available to cybercriminals after being integrated into an open-source testing tool.
Researchers say a previously unknown hole in IE has already been used to deliver a trojan in real-world attacks.
With no fix available yet, Microsoft has a few words of wisdom for users who don't want to be bit by the newly-discovered bug.
Pure Hacking's Gordon Maddern, a tech security writer, has uncovered a zero-day vulnerability affecting Mac users of the popular chat platform Skype.
Patch Tuesday for March will include a "critical" bulletin affecting Windows and "important" bulletins for Windows and Office.
The software giant says that fixing the flaw earlier would have broken customer network applications.
The software maker says that it is looking into an issue that may leave many Windows programs subject to an attack mechanism known as DLL preloading, or binary planting.
While Windows, OS X, and Linux platforms may be affected, this effort is a crude and easily detectable attempt.
Security researcher says vulnerability in Windows 7 could lead to an attack causing a critical system error, or "blue screen of death."