The bugs keep marching in, with Microsoft, McAfee, and Mozilla all having to deal with serious security-related software problems in the past month.
Another Windows Fix
According to Microsoft, "two privately reported vulnerabilities in Windows Authenticode Verification...could allow remote code execution." In other words, an attacker could take control of your PC by exploiting either of those flaws. The intruder could gain administrator rights, with the ability to add, change, or delete practically any file.
Microsoft has issued an update that addresses the vulnerabilities by performing additional verification operations. This update is critical to all supported versions of Windows, including 98, XP, Vista, and 7, as well as Server 2003, 2008, 2008 R2, 2003, 2000, and 2000 Professional.
If you have automatic updates enabled (recommended), you'll get this update and others instantly. If you do not have automatic updating turned on, Microsoft suggests downloading critical updates manually; go to the Control Panel, click the Windows Update icon, and then select Check for Updates. You can learn more about this patch, and download it manually, at Microsoft TechNet.
McAfee Update Makes Windows PCs Crash
McAfee released an update in mid-April that unfortunately caused Windows PCs to fail spectacularly. The update improperly identified a Windows component known as svchost.exe as a virus, which caused McAfee's software to delete it.
The error was so severe that 8000 of the 25,000 computers at the University of Michigan Health System and Medical School crashed, along with thousands of computers around the world.
Put simply, svchost.exe is a process that hosts other services used by various programs on your PC (read Microsoft's explanation for more-technical details). If you look in Windows Task Manager, you may see quite a few svchost.exe processes running (under "Image Name"), and as you can imagine, attacking all of them could be catastrophic for any system.
The problematic update mostly affected users running Windows XP Service Pack 3. If it affected you, pick up McAfee's SuperDAT Remediation Tool to restore svchost.exe.
Firefox Flaw Corrected
A hole in the Mozilla Firefox Web browser has blossomed into a major flaw. A week after releasing Firefox 3.6.2, Mozilla released version 3.6.3 to address a critical security issue that could allow remote attackers to run commands of their choice.
To fix the bug, download Firefox 3.6.3, or click Help, Check for Updates, Get the New Version in the Firefox toolbar. Mozilla says the bug does not affect versions 3.5 or earlier.
If you still want to obtain and use add-ons that are not compatible with version 3.6, don't worry: Mozilla says that it will issue a patch for Firefox 3.5 in an upcoming release in case another method of exploiting this security hole exists.