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.

About Cross Site Scripting – Roundcube Webmail (CVE-2024-37383) vulnerability

About Cross Site Scripting - Roundcube Webmail (CVE-2024-37383) vulnerability

About Cross Site Scripting – Roundcube Webmail (CVE-2024-37383) vulnerability. Roundcube is a web-based email client with functionality comparable to desktop email clients such as Outlook Express or Mozilla Thunderbird.

The vulnerability is caused by an error in the processing of SVG elements in the email body. The victim opens an email from the attacker, which causes malicious JavaScript code to be executed in the context of the user’s page.

In September 2024, specialists from the TI department of the Positive Technologies Expert Security Center (PT ESC) discovered a malicious email with signs of exploitation of this vulnerability. It was sent to one of the government agencies of the CIS countries.

Attacks on Roundcube are not uncommon. At the end of last year, there were news about the exploitation of a similar vulnerability CVE-2023-5631 in targeted attacks.

Update it in a timely manner!

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Veeam B&R RCE vulnerability CVE-2024-40711 is exploited in attacks

Veeam B&R RCE vulnerability CVE-2024-40711 is exploited in attacks

Veeam B&R RCE vulnerability CVE-2024-40711 is exploited in attacks. On September 24, there were no signs of this vulnerability being exploited in the wild. And on October 10, Sophos X-Ops reported that they had observed a series of attacks exploiting this vulnerability over the course of a month. The attackers’ goal was to install Akira and Fog ransomware. 🤷‍♂️

The thesis of my original post was correct. The absence of reports on the exploitation of vulnerabilities in real attacks is not a reason to ignore them.

“This does not mean that attackers do not exploit these vulnerabilities. It is possible that targeted attacks using these vulnerabilities have simply not yet been reliably confirmed.”

🟥 Positive Technologies classifies the vulnerability as trending since September 10th.

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Ford won’t work?

Ford won't work?

Ford won’t work? There were a lot of comments about “paying vulnerability fixers only when they are in the break room“. I’ll say right away that the post was a joke. Staff motivation is too delicate a topic to give serious recommendations. 🙂

But I will sort out the objections:

🔻 IT staff will sabotage the vulnerability detection process by tweaking host configs. So that the scanner will produce only green reports. But IT staff can do this at any time, and we need to take this into account. 🤷‍♂️

🔻 IT staff will simply turn off hosts. If they can do this without harming the business, that’s great. 👍 And if this will break the production environment, then let them deal with their IT management. 😏

🔻 There is an opinion that the method is good, but only 2% of vulnerabilities used in attack chains need to be fixed. I traditionally DO NOT agree with the possibility of reliably separating these mythical 2% of vulnerabilities. Everything needs to be fixed. 😉

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October Microsoft Patch Tuesday

October Microsoft Patch Tuesday

October Microsoft Patch Tuesday. 146 CVEs, of which 28 were added since September MSPT. 2 vulnerabilities with signs of exploitation in the wild:

🔻 Remote Code Execution – Microsoft Management Console (CVE-2024-43572)
🔻 Spoofing – Windows MSHTML Platform (CVE-2024-43573)

Without signs of exploitation in the wild, but with a public PoC exploit:

🔸 Remote Code Execution – Open Source Curl (CVE-2024-6197)

Private exploits exist for:

🔸 Information Disclosure – Microsoft Edge (CVE-2024-38222)
🔸 Security Feature Bypass – Windows Hyper-V (CVE-2024-20659)

Among the rest can be highlighted:

🔹 Remote Code Execution – Remote Desktop Protocol Server (CVE-2024-43582)
🔹 Remote Code Execution – Windows Remote Desktop Client (CVE-2024-43533, CVE-2024-43599)
🔹 Remote Code Execution – Windows Routing and Remote Access Service (RRAS) (CVE-2024-38212 and 11 more CVEs)

🗒 Full Vulristics report

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Attack on the complainer

Attack on the complainer

Attack on the complainer. Let’s say you ordered a product or service from some organization (marketplace, online store, service center – it doesn’t matter) and something went wrong. It’s quite natural to find the official community of this organization on a social network and write a complaint. Communication with the support team is good, but with some public stimulation it’s even better, right? 😉

Only since the complaint is public, it can be read not only by the organization’s employees, but also by attackers. 🤷‍♂️ They can write to you in a private message, posing as a representative of the organization, and promise to resolve all issues.

You just need to
🔻 go to the website (a phishing one 🪝)
🔻 fill out the form (with personal and card data 💳)
🔻 enter SMS code (2FA from Government Services website 🛂)
🔻 download and run the “helper application” (malware 👾)

There can be many attack scenarios. And there is only one way to resist them – vigilance.

На русском

Vulnerability Remediation using the “Ford Method”

Vulnerability Remediation using the Ford Method

Vulnerability Remediation using the “Ford Method”. There is a popular story in the Russian segment of the Internet. Allegedly, an experiment was carried out at Henry Ford’s plant: conveyor repair workers were paid only for the time they were in the break room. And as soon as the conveyor stopped 🚨 and the repair workers went to fix it, they stopped getting paid. Therefore, they did their work quickly and efficiently, so that they could quickly (and for a long time) return to the break room and start earning money again. 👷‍♂️🪙

I did not find any reliable evidence of this. 🤷‍♂️

But what if the specialists responsible for vulnerability remediation were paid only for the time when vulnerabilities are not detected on their hosts. 🤔 This can have a very positive impact on the speed and quality of remediation. Unsolvable problems will quickly become solvable, and automation of testing and deployment of updates will develop at the fastest pace. 😏

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Continuing the story about recent CUPS vulnerabilities: vulnerable hosts will be used by attackers to amplify DDoS attacks

Continuing the story about recent CUPS vulnerabilities: vulnerable hosts will be used by attackers to amplify DDoS attacks

Continuing the story about recent CUPS vulnerabilities: vulnerable hosts will be used by attackers to amplify DDoS attacks.

Researchers from Akamai Technologies wrote about this. An attacker can send a special packet to a vulnerable host with CUPS: “add a printer located at this IP address”. CUPS will start sending large IPP/HTTP requests to the specified IP address. Thus, vulnerable hosts can be organized in such a way that they start DDoSing IP addresses chosen by the attacker.

Akamai has discovered more than 198,000 vulnerable hosts with CUPS, of which more than 58,000 (34%) can be used for DDoS attacks. Of these, hundreds demonstrated an “infinite loop” of requests in response to HTTP/404.

Assuming that all 58,000+ vulnerable hosts are used for the attack, they can cause a traffic flow of 1 GB to 6 GB per attacker’s udp packet. The victim will have to handle 2.6 million TCP connections and HTTP requests.

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