Editor's Note: Dave Kearns is traveling this week and will be back next week. In place of his usual newsletter, we bring you breaking Windows networking\u00a0news from Networkworld.com.Microsoft is warning of two bugs in its software that could potentially give unauthorized control or access over a person's computer, while a third problem has been highlighted by a security research company.One vulnerability revisits the Windows Metafile (WMF) debacle from December, but impacts fewer users. The bug is in Internet Explorer (IE) 5.01 Service Pack 4 on the Windows 2000 Service Pack 4 OS and IE 5.5 Service Pack 2 on Windows Millennium, Microsoft said.An attacker could gain control if a user opened a malicious e-mail attachment or if a user were persuaded into visiting a Web site that had a specially-crafted WMF image, Microsoft said.A patch has not been issued, but Microsoft said the issue is under investigation, and an out-of-cycle patch could be provided depending on customer needs. Microsoft typically issues patches on the second Tuesday of the month, due this month on Feb. 14.A second vulnerability could allow a person with low-user privileges gain higher-level access, Microsoft said. Proof-of-concept code that has been released attempts to exploit overly permissive access controls on third-party application services, along with the default services of Windows XP Service Pack 1 and Windows Server 2003, the company said. No attacks have been reported.Microsoft said several factors diminish the threat of the problem. Those running Windows XP Service Pack 2 and Windows Server 2003 Service Pack 1 - the latest updates of the software - are not affected, and someone who launches an attack would need authenticated access to the affected operating system, it said.Security vendor Secunia detailed a third vulnerability involving Microsoft's HTML Help Workshop, software that can create online help for a software application or Web site content.Secunia said the problem "is caused due to a boundary error within the handling of a '.hhp' file that contains an overly long string in the 'contents file' field. This can be exploited to cause a stack-based buffer overflow and allows arbitrary code execution when a malicious '.hhp' file is opened."The bug could allow arbitrary code to be executed on a computer, Secunia said. An exploit has been released, and Secunia advised that untrusted .hhp files not be opened.Jeremy Kirk is a correspondent with the IDG News Service, a Network World affiliate.