Tag Archives: Windows

Microsoft Patch Tuesday December 2021

Microsoft Patch Tuesday December 2021. Hello everyone! It’s even strange to talk about other vulnerabilities, while everyone is so focused on vulnerabilities in log4j. But life doesn’t stop. Other vulnerabilities appear every day. And of course, there are many critical ones among them that require immediate patching. This episode will be about Microsoft Patch Tuesday for December 2021.

I will traditionally use my open source Vulristics tool for analysis.

Continue reading

Last Week’s Security news: Serious Sam in Metasploit, PetitPotam, Zimbra Hijack, Joint Advisory TOP30 CVEs

Last Week’s Security news: Serious Sam in Metasploit, PetitPotam, Zimbra Hijack, Joint Advisory TOP30 CVEs. Hello everyone! Last Week’s Security News, July 26 – August 1.

Serious Sam in Metasploit

Last week I talked about the Serious Sam vulnerability (CVE-2021-36934), also known as HiveNightmare. The name HiveNightmare comes from the fact that Windows stores its registry data in a small number of proprietary database files called hives. Due to mismanagement of SAM and SYSTEM hives in Windows 10, it is possible for an unprivileged user to read those files and then, for example, extract the account password hashes. An exploit for this vulnerability is now available in Metasploit and it will be much easier for attackers to exploit this vulnerability. The issues is still under investigation by Microsoft and a patch is not currently available, only the list of vulnerable OS versions, however a workaround has been provided.

PetitPotam

At the beginning of last week, PetitPotam (Little Hippo) attack made a lot of noise. It could force remote Windows systems to reveal password hashes that could then be easily cracked.

“The PetitPotam bug is tied to the Windows operating system and the abuse of a remote access protocol called Encrypting File System Remote Protocol (MS-EFSRPC). The protocol is designed to allow Windows systems to access remote encrypted data stores, allowing for management of the data while enforcing access control policies. […]
The PetitPotam PoC is a form of manipulator-in-the-middle (MitM) attack against Microsoft’s NTLM authentication system. Next, an attacker uses the file-sharing protocol Server Message Block (SMB) to request access to a remote system’s MS-EFSRPC interface. According to [security researcher Gilles Lionel], this forces the targeted computer to initiate an authentication procedure and share its authentication details via NTLM.

In response to the public availability of the PoC, Microsoft was quick to respond, outlining several mitigation options. For starters, Microsoft recommends disabling NTLM authentication on Windows domain controllers. It also suggests enabling the Extended Protection for Authentication (EPA) feature on AD CS services.”

But there won’t be any special fix. Microsoft: “PetitPotam is a classic NTLM Relay Attack, and such attacks have been previously documented by Microsoft along with numerous mitigation options to protect customers.”

Continue reading

Last Week’s Security news: Pegasus, SeriousSAM, Sequoia

Last Week’s Security news: Pegasus, SeriousSAM, Sequoia. Hello everyone! After 4 episodes of the Last Week’s Security news, I decided to change the format. I will no longer try to cover all the important news, because it takes a long time to prepare such reviews. So, from now on, I will focus only on a few news of the past week, which I subjectively consider the most interesting.

So, the last week, July 19 – July 25. In my opinion, the most interesting news was the scandal related to the iPhone Pegasus spyware and two Elevations of Privileges: SeriousSAM for Windows and Sequoia for Linux.

Continue reading

Vulristics Microsoft Patch Tuesday July 2021: Zero-days EoP in Kernel and RCE in Scripting Engine, RCEs in Kernel, DNS Server, Exchange and Hyper-V

Vulristics Microsoft Patch Tuesday July 2021: Zero-days EoP in Kernel and RCE in Scripting Engine, RCEs in Kernel, DNS Server, Exchange and Hyper-V. Hello everyone! For the past 9 months, I’ve been doing Microsoft Patch Tuesday reviews quarterly. Now I think it would be better to review the July Patch Tuesday while the topic is still fresh. And that will save us some time in the next Last Week’s Security news episode. So, July Patch Tuesday, 116 vulnerabilities.

The 2 most critical are the Windows Kernel Elevation of Privilege Vulnerabilities (CVE-2021-31979, CVE-2021-33771). These vulnerabilities are critical because they are used in real attacks according to Microsoft’s Threat Intelligence Center and Security Response Center. Tenable: “A local, authenticated attacker could exploit these vulnerabilities to run processes with elevated permissions. Similar zero-day vulnerabilities were patched in April 2020, which were observed under active exploitation by Google Project Zero.”

Continue reading

Getting Hosts from Microsoft Intune MDM using Python

Getting Hosts from Microsoft Intune MDM using Python. Today I want to talk about Microsoft Intune. It is a Mobile Device Management platform.

Well, I think that the importance of MDM systems has become much higher than it was before the days of covid-19. Simply because a lot more people now work remotely using corporate laptops. And if these people don’t connect to the corporate network using a VPN, you most likely won’t see any activity from their devices in Active Directory. This means that you will not understand whether the device is active or not. And it will be impossible to get the correct security metrics for these devices.

Mobile device management is a solution to this problem as it maintains a connection between the laptop and the cloud server. MDM can collect various parameters from hosts, but for me the most important parameter is the timestamp. I will not describe all the features of Microsoft Intune here. Simply because at this stage they are not very interesting to me. The task I needed to solve was how to get the timestamp of the last activity for all hosts in Microsoft Intune using the official API. And since this is poorly documented, I want to share it with you.

Continue reading

Vulristics: Beyond Microsoft Patch Tuesdays, Analyzing Arbitrary CVEs

Vulristics: Beyond Microsoft Patch Tuesdays, Analyzing Arbitrary CVEs. Hello everyone! In this episode I would like to share an update for my Vulristics project.

For those who don’t know, in this project I am working on an alternative vulnerability scoring based on publicly available data to highlight vulnerabilities that need to be fixed as soon as possible. Roughly speaking, this is something like Tenable VPR, but more transparent and even open source. Currently it works with much less data sources. It mainly depends on the type of vulnerability, the prevalence of vulnerable software, public exploits and exploitation in the wild.

Elevation of Privilege - Windows Win32k

I started with Microsoft PatchTuesday Vulnerabilities because Microsoft provides much better data than other vendors. They have the type of vulnerability and the name of the vulnerable software in the title.

Elevation of Privilege - Windows Win32k MS site

But it’s time to go further and now you can use Vulristics to analyze any set of CVEs. I changed the scirpts that were closely related to the Microsoft datasource and added new features to get the type of vulnerability and name of the software from the CVE description.

Elevation of Privilege - Sudo (CVE-2021-3156) - High [595]

Continue reading

Microsoft Patch Tuesday September 2020: Zerologon and other exploits, RCEs in SharePoint and Exchange

Microsoft Patch Tuesday September 2020: Zerologon and other exploits, RCEs in SharePoint and Exchange. I would like to start this post by talking about Microsoft vulnerabilities, which recently turned out to be much more serious than it seemed at first glance.

Older Vulnerabilities with exploits

“Zerologon” Netlogon RCE (CVE-2020-1472)

One of them is, of course, the Netlogon vulnerability from the August 2020 Patch Tuesday. It’s called “Zerologon”. I would not say that Vulnerability Management vendors completely ignored it. But none of them (well, maybe only ZDI) emphasized in their reports that this vulnerability would be a real disaster.

Continue reading