Let’s start with Microsoft’s August Patch Tuesday. I think the most interesting thing is that it contains a fix for the PetitPotam vulnerability. I talked about this vulnerability two weeks ago. At the time, Microsoft had no plans to release a patch because PetitPotam was a “classic NTLM Relay Attack”. But the patch was actually released as part of August Patch Tuesday.
A quote from Rapid7: “Tracked as CVE-2021-36942, the August 2021 Patch Tuesday security update blocks the affected API calls OpenEncryptedFileRawA and OpenEncryptedFileRawW through the LSARPC interface”.
There are no formal signs that this vulnerability is critical other than comments from the vendors. My Vulristics tool has flagged this “Windows LSA Spoofing” as a Medium level Vulnerability. But this fix seems to be the most important thing in this Patch Tuesday. So install this patch first.
Hello everyone! In this episode, I would like to tell you how I tried to get automatically antivirus-related data (current status, engine and signature version, last full scan date) from Microsoft Defender for Endpoint using Microsoft Intune and the Graph API.
Why is this necessary?
You might assume that if the Defender for Endpoint agent is installed on the host, everything should be fine automatically. But in fact, the antivirus engine and signature versions may be outdated, real-time protection may be disabled. And so all this needs to be monitored.
Grapf API
This will be the third episode about Microsoft Enterprise Security APIs. The first was about Defender and Defender API, the second was about Intune and the Intune API. And today I’m going to talk about the Grapf API, which should probably replace all the other APIs and should be more logical and easier. Although in my opinion it is even strangier and poorly documented. I didn’t like it.
Hello everyone! Last Week’s Security News, August 1 – August 8.
Black Hat Pwnie Awards
Last week was more quiet than normal with Black Hat USA and DEF CON security conferences. I would like to start with the Pwnie Awards, which are held annually at Black Hat. It’s like an Oscar or Tony in the information security world. Pwnie Awards recognizes both excellence and incompetence. And, in general, is a very respectable, adequate and fun event.
Firstly 2 nominations, which were received by the guys from Qualys. Best Privilege Escalation Bug: Baron Samedit, a 10-year-old exploit in sudo. Most Under-Hyped Research: 21Nails, 21 vulnerabilities in Exim, the Internet’s most popular mail server.
Best Server-Side Bug: Orange Tsai, for his Microsoft Exchange Server ProxyLogon attack surface discoveries.
Most Epic Fail: Microsoft, for their failure to fix PrintNightmare.
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.”
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.
The Gartner Vulnerability Management Reports are one of the few marketing reports that I try to read regularly. This started back in the days when I was working for a VM vendor doing competitive analysis. Gartner is one of the few organizations that think about Vulnerability Assessment and Vulnerability Management and clearly articulate where we are and where we are going.
I got a free reprint of “2021 Gartner Market Guide for Vulnerability Assessment” from the Tenable website. Thanks a lot to them for that.
Let’s start with what I liked:
It’s great that Gartner has made vulnerability prioritization technology (VPT) a separate class of solutions, that do not detect vulnerabilities themselves, but work with them. For example, Kenna or my Vulristics. And it could be additional functionality like Tenable VPR.
I liked the focus on EDR as a promising VM replacement. Especially, Microsoft solutions (Defender for Endpoint or as was mentioned in the report Microsoft’s Threat & Vulnerability Management, TVM).
It’s nice that various areas related to Vulnerability Management have been mentioned: Pentest, Bug Bounty, Breach and Attack Simulation (BAS).
An interesting diagram that shows that VA is primarily about “Assess” and “Asset Management”, VPT is primarily about “Prioritize” and “Workflow Management”, BAS is primarily about “Compensate” and “Security Controls”.
Now what I didn’t like. I have one pain point – the quality of the scanning. And here, on the one hand, something was said, but on the other, it was not enough and not as definite as I would like. Market Direction is the most interesting section of the document. And it was the most painful to read.
This is my personal blog. The opinions expressed here are my own and not of my employer. All product names, logos, and brands are property of their respective owners. All company, product and service names used here for identification purposes only. Use of these names, logos, and brands does not imply endorsement. You can freely use materials of this site, but it would be nice if you place a link on https://avleonov.com and send message about it at me@avleonov.com or contact me any other way.
