monthly cycle

Bad timing:

In its latest monthly update, Microsoft was not been able to fix a serious vulnerability in Internet Explorer because the flaw was discovered only a few days before the company�s regular update was due. To make matters worse a worm exploiting the flaw was released on Monday, leaving the software giant without any option but to ignore the problem � for now.
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The IFRAME vulnerability and the Bofra worm appeared in the week leading up to the final release of Mozilla�s Firefox browser, which is unaffected by the worm and seen as the biggest threat to Microsoft�s dominance of the browser market for many years.