Patch Tuesday March 2018

BeyondTrust Research Team
March 14th, 2018

patch tuesday

Welcome back to the March 2018 Patch Tuesday. Microsoft has released updates for the usual suspects of software, and Adobe has issued fixes as well. None of these vulnerabilities have been reported to be exploited in the wild, but vulnerabilities from Exchange Server and ASP.NET Core 2.0 (CVE-2018-0940 and CVE-2018-0808 respectively) had been disclosed before these patches were available.

Kernel

The Windows Kernel has received a handful of fixes. The vulnerabilities that these fixes patch allow for a successful exploit to elevate an attacker’s privileges on a system and disclose sensitive information that could further compromise an affected system. The vulnerabilities revolve around object memory mismanagement at the kernel level. Microsoft rates these vulnerabilities as “Important.”

Hyper-V

Microsoft’s native Hypervisor has received and update for x64 based systems. The vulnerability would have allowed for a user on a guest operating system to gain information on the host. A real-world example of this would be if a cloud VM user were to use their VM maliciously to gain information on the cloud server itself, possibly compromising another user’s information. Additionally, a guest operating system could cause denial-of-service conditions by running a malicious application on the guest system, resulting in the host system crashing. Microsoft rates these vulnerabilities as “Important”.

Remote Assistance Tool

An Information Disclosure vulnerability was patched for Microsoft’s Remote Assistance tool. The vulnerability revolved around the incorrect parsing of XML External Entities (XXE), which could be leveraged to obtain sensitive information. An attacker would have to convince the victim to accept a specially crafted Remote Assistance file. This vulnerability is particularly interesting since it stems from remote assistance files, which are intended to help typically less-savvy users, making them precisely the right target for social engineering. Microsoft rates this vulnerability as “Important”.

Office

Office was host to a dizzying number of fixes this month. In total, 18 vulnerabilities across a myriad of products were fixed. The impact of these vulnerabilities ranged from remote code execution, information leaks, spoofing, and denial of service. The Exchange Server vulnerability that was publicly disclosed prior to patching was a result of failing to properly sanitize links presented to users, allowing for a fake login pages to be presented that would attempt to trick users into disclosing valid logins. Microsoft rates these vulnerabilities as “Important”.

Edge and Internet Explorer

Edge and Internet Explorer contained all this month’s Critical rated vulnerabilities. The two Critical vulnerabilities, CVE-2018-0889 and CVE-2018-0932, had the impacts of remote code execution and information disclosure respectively. Both vulnerabilities resulted from object memory mishandling. An attacker attempting to exploit these vulnerabilities would have to host maliciously crafted content on a web server, and convince the victim to visit that server via phishing or social engineering.

Adobe Flash Player

As usual the Adobe Flash Player lives on in infamy with bugs needing to be fixed. The latest round involves fixing two Remote Code Execution vulnerabilities that Adobe rates as Critical. The vulnerabilities result from a Use-After-Free object memory error, and a Type-Confusion error. Adobe plans on retiring Flash Player in 2020, but it is advisable to simply remove the software from a system if the system does not require it.

BeyondTrust Research Team

The BeyondTrust Research Team is known for identifying new trends in enterprise security, including some of the very first critical Microsoft security vulnerabilities. By providing in-depth research analysis of the latest and cutting-edge vulnerabilities, the team’s goal is to educate our customers on the evolving threat landscape while shaping the future of BeyondTrust’s privilege and vulnerability management solutions.