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 readingHello 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.
Continue readingHello 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, 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.
74 vulnerabilities: 1 Critical, 30 High, 43 Medium.
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.
Continue readingHello everyone! This is a new episode with my comments on the latest Information Security news.
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.
Continue readingHello 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 readingHello everyone! Let’s now talk about Microsoft Patch Tuesday vulnerabilities for the second quarter of 2021. April, May and June. Not the most exciting topic, I agree. I am surprised that someone is reading or watching this. For me personally, this is a kind of tradition. Plus this is an opportunity to try Vulristics in action and find possible problems. It is also interesting to see what VM vendors considered critical back then and what actually became critical. I will try to keep this video short.
First of all, let’s take a look at the vulnerabilities from the April Patch Tuesday. 108 vulnerabilities, 55 of them are RCEs. Half of these RCEs (27) are weird RPC vulnerabilities. “Researcher who reported these bugs certainly found quite the attack surface”. The most critical vulnerability is RCE in Exchange (CVE-2021-28480). This is not ProxyLogon, this is another vulnerability. ProxyLogon was in March. And this vulnerability is simply related to ProxyLogon, so it is believed that it is exploited in the wild as well. In the second place this Win32k Elevation of Privilege (CVE-2021-28310). It is clearly mentioned in several sources as being used in real attacks. “Bugs of this nature are typically combined with other bugs, such as a browser bug or PDF exploit, to take over a system”. And the only vulnerability with a public exploit is the Azure DevOps Server Spoofing (CVE-2021-28459). Previously known as Team Foundation Server (TFS), Azure DevOps Server is a set of collaborative software development tools. It is hosted on-premises. Therefore, this vulnerability can be useful for attackers.
Continue readingHello everyone! It has been 3 months since my last review of Microsoft vulnerabilities for Q4 2020. In this episode I want to review the Microsoft vulnerabilities for the first quarter of 2021. There will be 4 parts: January, February, March and the vulnerabilities that were released between the Patch Tuesdays.
I will be using the reports that I created with my Vulristics tool. This time I’ll try to make the episodes shorter. I will describe only the most critical vulnerabilities. Links to the full reports are at the bottom of the blog post.
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