Category Archives: Vulnerability

Log4j “Log4Shell” RCE explained (CVE-2021-44228)

Log4j “Log4Shell” RCE explained (CVE-2021-44228). Hello everyone! I decided to make a separate episode about Log4Shell. Of course, there have already been many reviews of this vulnerability. But I do it primarily for myself. It seems to me that serious problems with Log4j and similar libraries will be with us for a long time. Therefore, it would be interesting to document how it all began. So what is the root cause of Log4Shell?

Logs

Generally speaking, the IT infrastructure of any company deals with streams of input data. From user requests to a corporate website to integration with banking APIs and cloud services. A lot of data gets into the infrastructure of the company, is transferred from system to system, periodically getting into the logs. These logs are required to verify that the systems are functioning correctly.

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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.

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Vulnerability Intelligence based on media hype. It works? Grafana LFI and Log4j “Log4Shell” RCE

Vulnerability Intelligence based on media hype. It works? Grafana LFI and Log4j “Log4Shell” RCE. Hello everyone! In this episode, I want to talk about vulnerabilities, news and hype. The easiest way to get timely information on the most important vulnerabilities is to just read the news regularly, right? Well, I will try to reflect on this using two examples from last week.

I have a security news telegram channel https://t.me/avleonovnews that is automatically updated by a script using many RSS feeds. And the script even highlights the news associated with vulnerabilities, exploits and attacks.

And last Tuesday, 07.02, a very interesting vulnerability in Grafana was released.

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Vulristics Command Line Interface, improved Product & Vuln. Type Detections and Microsoft Patch Tuesday November 2021

Vulristics Command Line Interface, improved Product & Vuln. Type Detections and Microsoft Patch Tuesday November 2021. Hello everyone! In this episode I want to highlight the latest changes in my Vulristics project. For those who don’t know, this is a utility for prioritizing CVE vulnerabilities based on data from various sources.. Currently Microsoft, NVD, Vulners, AttackerKB.

Command Line Interface

I started working on the CLI for Vulristics. Of course, it is not normal to edit scripts every time to release a report.

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Security News: Microsoft Patch Tuesday October 2021, Autodiscover, MysterySnail, Exchange, DNS, Apache, HAProxy, VMware vCenter, Moodle

Security News: Microsoft Patch Tuesday October 2021, Autodiscover, MysterySnail, Exchange, DNS, Apache, HAProxy, VMware vCenter, Moodle. Hello everyone! This episode will be about relatively recent critical vulnerabilities. Let’s start with Microsoft Patch Tuesday for October 2021. Specifically, with the vulnerability that I expected there, but it didn’t get there.

Autodiscover leak discovered by Guardicore Labs

“Autodiscover, a protocol used by Microsoft Exchange for automatic configuration of clients such as Microsoft Outlook, has a design flaw that causes the protocol to “leak” web requests to Autodiscover domains outside of the user’s domain but in the same TLD (i.e. Autodiscover.com).” Guardicore Labs acquired multiple Autodiscover domains and have captured 372,072 Windows domain credentials in total. It seems Microsoft have chosen to ignore this issue. No CVE, no Outlook or ActiveSync patches. The only fix is to ban the “Autodiscover.” domains on devices.

Microsoft Patch Tuesday for October 2021

74 vulnerabilities: 1 Critical, 30 High, 43 Medium.

Elevation of Privilege – Windows Kernel (CVE-2021-40449)

It is a use-after-free vulnerability in the NtGdiResetDC function of the Win32k driver. A detailed technical description is available in Kasperky Securelist post, but, in short, the vulnerability can lead to leakage of kernel module addresses in the computer’s memory. This vulnerability is being exploited in the wild by APT MysterySnail. All servers and desktops should be updated.

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Security News: Microsoft Patch Tuesday September 2021, OMIGOD, MSHTML RCE, Confluence RCE, Ghostscript RCE, FORCEDENTRY Pegasus

Security News: Microsoft Patch Tuesday September 2021, OMIGOD, MSHTML RCE, Confluence RCE, Ghostscript RCE, FORCEDENTRY Pegasus. Hello everyone! This time, let’s talk about recent vulnerabilities. I’ll start with Microsoft Patch Tuesday for September 2021. I created a report using my Vulristics tool. You can see the full report here.

The most interesting thing about the September Patch Tuesday is that the top 3 VM vendors ignored almost all RCEs in their reviews. However, there were interesting RCEs in the Office products. And what is most unforgivable is that they did not mention CVE-2021-38647 RCE in OMI – Open Management Infrastructure. Only ZDI wrote about this.

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Security News: Exchange ProxyShell, Zoom RCE, Citrix Canceled PT Acknowledgments, Cisco No Patch Router RCEs

Security News: Exchange ProxyShell, Zoom RCE, Citrix Canceled PT Acknowledgments, Cisco No Patch Router RCEs. Hello everyone! This is a new episode with my comments on the latest Information Security news.

Exchange ProxyShell

I want to start with something about attacks on Exchange. ProxyShell is in the news, the LockFile ransomware compromised more than 2000 servers. On the other hand, there is basically nothing to say here.

ProxyShell is the name for 3 vulnerabilities. The bulletins for Remote Code Execution CVE-2021-34473 and Server Elevation of Privilege CVE-2021-34523 were released on July 13, but were fixed by April Patch Tuesday patches. Yes, it happens sometimes. The bulletin for Security Feature Bypass CVE-2021-31207 was released on May 11. Users had 4 months to install the updates. Interestingly, 2 out of 3 vulnerabilities have the property “Less likely to be exploited”. As you can see, it’s pretty useless.

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