Microsoft May Patch Tuesday Addresses Windows, Office Flaws

Three of the seven bulletins issued by Microsoft are tagged "critical," while the other four are labeled "important."

Microsoft is continuing its trend this year of large numbers of monthly security patches, with the software giant on May 3 sending out seven bulletins that contain almost two-dozen security vulnerabilities related to Windows, Office, Silverlight and .NET Framework.

According to a notice issued by Microsoft, three of the bulletins are listed as €œcritical,€ while the other four are labeled €œimportant.€ These upgrades follow April, when Microsoft issued six bulletins, with four tagged as critical.

The three rated critical run the risk of remote code execution attacks, according to Microsoft. Two of the important bulletins also present the risk of remote code execution attacks, while the other two risk elevation of privileges, which means that users can move up their privileges to the administrator level if they have the necessary information.

All current versions of Windows will be affected by the patches, the company said in its notice.

Marcus Carey, security researcher at security software vendor Rapid7, said Microsoft€™s latest round of bulletins proves that even though there have been a lot of patches issued in previous months, users should not be surprised that another seven are being issued.

€œThe 'Microsoft Security Bulletin Advance Notification' for May 2012 contains seven bulletins: three rated €˜critical€™ and the rest €˜important,€ Carey wrote in an email. €œJust when most organizations and consumers have been fanning the flames of the first quarter, this serves notice that information security is a war and not a battle.€

Microsoft is scheduled to issue the patches May 8.

Bulletin 1 addresses a critical vulnerability in Office, and Carey suggested the flaw most likely could be exploited by creating a malicious file that can be opened by Office applications.

€œThis is becoming a recurring theme for organizations and end users because it's primed for phishing attacks,€ he wrote. €œAs we€™ve learned over the past couple weeks, Mac users need to apply these patches as soon as possible as attackers are targeting them through Microsoft Office vulnerabilities.€

Both Bulletins 2 and 3€”labeled critical€”impact all current Windows operating systems, from XP SP3 to Windows Server 2008, casting a wide net over businesses, given the high number that run Windows environments.

Bulletins 4 and 5 are both tagged important, both impact Office applications, and both, if exploited, could result in remote code execution attacks.

€œLabeling these bulletins as important indicates that an attacker will only inherit the permissions of the user,€ Carey wrote. €œThis means if a user is not an administrator, it's a somewhat lower risk. However, if a user has administrator privileges, these types of flaws can have the same impact as a critical rating.€

Bulletins 6 and 7, both also tagged as important, can€”if compromised€”enable cyber-criminals to leverage the escalation of privileges to get into an organization€™s systems.