Author Archives: Alexander Leonov

About Alexander Leonov

Hi! My name is Alexander and I am a Vulnerability Management specialist. You can read more about me here. Currently, the best way to follow me is my Telegram channel @avleonovcom. I update it more often than this site. If you haven't used Telegram yet, give it a try. It's great. You can discuss my posts or ask questions at @avleonovchat. А всех русскоязычных я приглашаю в ещё один телеграмм канал @avleonovrus, первым делом теперь пишу туда.

Joint Advisory AA22-279A and Vulristics

Hello everyone! This episode will be about the new hot twenty vulnerabilities from CISA, NSA and FBI, Joint cybersecurity advisory (CSA) AA22-279A, and how I analyzed these vulnerabilities using my open source project Vulristics.

Alternative video link (for Russia): https://vk.com/video-149273431_456239105

Americans can’t just release a list of “20 vulnerabilities most commonly exploited in attacks on American organizations.” They like to add geopolitics and point the finger at some country. Therefore, I leave the attack attribution mentioned in the advisory title without comment.

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How to Perform a Free Ubuntu Vulnerability Scan with OpenSCAP and Canonical’s Official OVAL Content

Hello everyone! Five years ago I wrote a blogpost about OpenSCAP. But it was only about the SCAP Workbench GUI application and how to use it to detect security misconfigurations.

Alternative video link (for Russia): https://vk.com/video-149273431_456239104

This time, I will install the OpenSCAP command line tool on Ubuntu and use it to check for vulnerabilities on my local host.

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Microsoft Patch Tuesday September 2022: CLFS Driver EoP, IP packet causes RCE, Windows DNS Server DoS, Spectre-BHB

Hello everyone! Let’s take a look at Microsoft’s September Patch Tuesday. This time it is quite compact. There were 63 CVEs released on Patch Tuesday day. If we add the vulnerabilities released between August and September Patch Tuesdays (as usual, they were in Microsoft Edge), the final number is 90. Much less than usual.

Alternative video link (for Russia): https://vk.com/video-149273431_456239101

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Scanvus – my open source Vulnerability Scanner for Linux hosts and Docker images

Hello everyone! This video was recorded for the VMconf 22 Vulnerability Management conference, vmconf.pw. I will be talking about my open source project Scanvus. This project is already a year old and I use it almost every day.

Alternative video link (for Russia): https://vk.com/video-149273431_456239100

Scanvus (Simple Credentialed Authenticated Network VUlnerability Scanner) is a vulnerability scanner for Linux. Currently for Ubuntu, Debian, CentOS, RedHat, Oracle Linux and Alpine distributions. But in general for any Linux distribution supported by the Vulners Linux API. The purpose of this utility is to get a list of packages and Linux distribution version from some source, make a request to an external vulnerabililty detection API (only Vulners Linux API is currently supported), and show the vulnerability report.

Scanvus can show vulnerabilities for

  • localhost
  • remote host via SSH
  • docker image
  • inventory file of a certain format

This utility greatly simplifies Linux infrastructure auditing. And besides, this is a project in which I can try to implement my ideas on vulnerability detection.

Example of output

For all targets the output is the same. It contains information about the target and the type of check. Then information about the OS version and the number of Linux packages. And finally, the actual information about vulnerabilities: how many vulnerabilities were found and the criticality levels of these vulnerabilities. The table shows the criticality level, bulletin ID, CVE list for the bulletin, and a comparison of the invulnerable fixed package version with the actual installed version.

This report is not the only way to present results. You can optionally export the results to JSON (OS inventory data, raw vulnerability data from Vulners Linux API or processed vulnerability data).

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Microsoft Patch Tuesday August 2022: DogWalk, Exchange EOPs, 13 potentially dangerous, 2 funny, 3 mysterious vulnerabilities

Hello everyone! In this episode, let’s take a look at the Microsoft Patch Tuesday August 2022 vulnerabilities. I use my Vulristics vulnerability prioritization tool as usual. I take comments for vulnerabilities from Tenable, Qualys, Rapid7, ZDI and Kaspersky blog posts. Also, as usual, I take into account the vulnerabilities added between the July and August Patch Tuesdays.

Alternative video link (for Russia): https://vk.com/video-149273431_456239098

There were 147 vulnerabilities. Urgent: 1, Critical: 0, High: 36, Medium: 108, Low: 2.

There was a lot of great stuff this Patch Tuesday. There was a critical exploited in the wild MSDT DogWalk vulnerability, 3 critical Exchange vulnerabilities that could be easily missed in prioritization, 13 potentially dangerous vulnerabilities, 2 funny vulnerabilities and 3 mysterious ones. Let’s take a closer look.

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Vulnerability Management news and publications #2

Hello everyone! This is the second episode of Vulnerability Management news and publications. In fact, this is a collection of my posts from the avleonovcom and avleonovrus telegram channels. Therefore, if you want to read them earlier, subscribe to these channels.

The main idea of ​​this episode. Microsoft is a biased company. In fact, they should now be perceived as another US agency. Does this mean that we need to forget about Microsoft and stop tracking what they do? No, it doesn’t. They do a lot of interesting things that can at least be researched and copied. Does this mean that we need to stop using Microsoft products? In some locations (you know which ones) for sure, in some we can continue to use such products if it is reasonable, but it’s necessary to have a plan B. And this does not only apply to Microsoft. So, it’s time for a flexible approaches. Here we do it this way, there we do it differently. It seems that rather severe fragmentation of the IT market is a long-term trend and it’s necessary to adapt to it.

Alternative video link (for Russia): https://vk.com/video-149273431_456239097

What’s in this episode:

  1. Microsoft released a propaganda report, what does this mean for us?
  2. Microsoft released the Autopatch feature, is it a good idea to use it?
  3. Ridiculous Vulnerability: Hardcoded Password in Confluence Questions
  4. The new Nessus Expert and why it’s probably Tenable’s worst release
  5. Rapid7 Nexpose/InsightVM features added in Q2 2022: what’s good and what’s weird
  6. Palo Alto: Malicious scan 15 minutes after CVE is released. Oh really?
  7. 6 groups of vulnerabilities that are most often used in attacks, according to Palo Alto, and the end of IT globalization
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Microsoft Patch Tuesday July 2022: propaganda report, CSRSS EoP, RPC RCE, Edge, Azure Site Recovery

Hello everyone! Microsoft has been acting weird lately. I mean the recent publication of a propaganda report about evil Russians and how Microsoft is involved in the conflict between countries. It wouldn’t be unusual for a US government agency, NSA or CIA to publish such a report. But when a global IT vendor, which, in theory, should be more or less neutral, does this… This is a clear signal. It’s not about business anymore.

Alternative video link (for Russia): https://vk.com/video-149273431_456239096

I’ll take a closer look at this report in the next episode of the Vulnerability Management news, but for now let’s take a look at Microsoft July Patch Tuesday. Yes, the vendor is behaving strangely, but Microsoft products need to be patched. Right? At least for now. And tracking vulnerabilities is always a good thing. 🙂

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