This month’s Patch Tuesday round from Microsoft features nine bulletins fixing 56 vulnerabilities including a mammoth 41 flaws in Internet Explorer.
The nine patches this month include four remote code execution flaws, two security feature bypasses, one escalation of privilege and one information disclosure vulnerability.
Six are rated ‘important’ by Redmond and three are ‘critical’, including MS15-009, which fixes one publicly reported and 40 privately reported flaws in Internet Explorer.
After unusually receiving no patches last month, the bug-ridden browser is back with a bang in February, with all versions affected.
“While one of the vulnerabilities is being used in the wild, it is not of the RCE type, but ‘only’ an Information Disclosure that attackers are using in conjunction with other vulnerabilities to gain control over the targeted machines,” explained Qualys CTO Wolfgang Kandek in a blog post.
However, the patch did not fix a universal cross-site scripting vulnerability discovered earlier this month by Deusen which could allow attackers to steal user credentials.
Next up is patch MS15-010, which is designed to fix one publicly disclosed and five privately reported vulnerabilities in Microsoft Windows, including a RCE flaw which could be exploited if an attacker convinces a user to visit a specially crafted doc or web page that contains embedded TrueType fonts.
The publicly disclosed vulnerability in this patch, CVE-2015-0010, was released by Google’s Project Zero team after its 90-day embargo period expired, but Microsoft said it is unaware of any exploitation attempts.
The final critical patch, MS15-011 affects all supported versions of Windows with remote code execution.
“The attacker has to trick a user to connect their client machine to the attacker’s malicious domain, which places the attack squarely into the enterprise realm, with the attacker controlling the domain controller or able to pose as domain controller,” explained Kandek.
“Interestingly enough Microsoft is not addressing the vulnerability in Windows Server 2003, but states that the fix would be too invasive to guarantee 2003 continued functioning. One more reason to get off the Server 2003 platform as soon as possible, in addition to the coming end-of-life of the platform in July of this year.”
The remaining six patches are rated ‘important’ and affect Office, Windows and Virtual Machine Manager.
One, MS15-016, relates to a flaw which could allow information disclosure if a user browses to a website containing a specially crafted TIFF image.
It could be used on a malicious website with the attacker able to see personal information about the user, according to Jon Rudolph, principal software engineer at Core Security.
“The good news is that they probably don’t get to pick what they see, and there is not a way to take control of the user’s system directly,” he added.
“However, as the information on our desktops and laptops becomes more vital over time, I think we’re more sensitive to information leaks like this and Heartbleed where attackers eavesdropping for long enough periods are bound to find the keys to our kingdoms and use them to fund and build castles of their own.”