zero-day

OpenSSL Downgrades Panic Bug After Days of Anxiety

Initial Report
On October 27th it was reported by Dark Reading that organizations have five days to get ready for what the OpenSSL Project defined as a “serious” vulnerability impacting versions 3.0 and up of the widely used cryptographic library for encrypting digital communications. They caution that enterprises would rush to remedy the problem as soon as possible if this vulnerability turns out to be another Heartbleed flaw, which was the most recent serious vulnerability to affect OpenSSL.

Favorable News
We now have some good news after five days since the initial revelations of an internet-reshaping major flaw in OpenSSL. Instead of the critical rating that initially alarmed the online community, CVE-2022-37786 and CVE-2022-3602 have been published as high-rated vulnerabilities. According to OpenSSL:

“A buffer overrun can be triggered in X.509 certificate verification, specifically in name constraint checking. Note that this occurs after certificate chain signature verification and requires either a CA to have signed the malicious certificate or for the application to continue certificate verification despite failure to construct a path to a trusted issuer. An attacker can craft a malicious email address to overflow four attacker-controlled bytes on the stack. This buffer overflow could result in a crash (causing a denial of service) or potentially remote code execution.”

As a result, the vulnerability is considerably harder to exploit than what was initially suggested.

Remediation
The two CVE reports published on November 1st indicate this issue as being present in OpenSSL versions 3.0.0 to 3.0.6. Despite the fact that these flaws are not as severe as anticipated, it is still advised that all businesses identify their OpenSSL implementations and update to version 3.0.7 right away. At this point, according to OpenSSL, there is no evidence that this vulnerability has been exploited in the wild and no operational exploit that could result in code execution. A list of notable operating systems and application runtimes which are packaged with a vulnerable version of OpenSSL has been established by the Computer Emergency Response Team (CERT) for the Netherlands.

What Now?
nGuard is ready to assist clients in detecting and mitigating OpenSSL vulnerabilities. nGuard can identify whether or not a vulnerable version of OpenSSL is present in your environment by performing vulnerability scans and penetration testing against both external and internal facing services. Organizations may feel at ease knowing that OpenSSL versions that are insecure are being fixed in their environments by carrying out these scans on a frequent basis.

TWiC | This Week in Cybersecurity

Over the past week there have been many hot topics in cybersecurity. This edition of This Week in Cybersecurity includes stories covering Microsoft patching the Follina Zero-Day, Apple M1 Kernel security flaws, a record-breaking DDoS attack, a Kaiser Permanente data breach, and US military hackers conducting offensive activities in support of Ukraine. Check out the details below.

Cloudflare Saw Record-Breaking DDoS Attack Peaking at 26 Million Request Per Second: Cloudflare disclosed that it had acted to prevent a record-setting 26 million requests per second (RPS) distributed denial-of-service (DDoS) attack last week, making it the largest HTTPS DDoS attack detected to date. In late April 2022, it said it staved off a 15.3 million RPS HTTPS DDoS attack aimed at a customer operating a crypto launchpad. According to the company’s DDoS attack trends report for Q1 2022, volumetric DDoS attacks over 100 gigabits per second surged by up to 645% quarter-on-quarter.
Microsoft Patches ‘Follina’ Zero-Day Flaw in Monthly Security Update: Microsoft has issued a patch for the recently disclosed and widely exploited “Follina” zero-day vulnerability in the Microsoft Support Diagnostic Tool as part of its scheduled security update for June. It’s a good idea for organizations to keep Microsoft’s recommended mitigations for the flaw in place even after they install the MSDT update. Applying the patch will protect users but the patch only fixed the code injection vulnerability in msdt.exe. The diagnostic tool itself will still launch if a user opens an affected document. For more information on this vulnerability, check out nGuard’s last Security Advisory: Microsoft Zero-Day with No Patch! This vulnerability will be commonly exploited via phishing attempts. Social Engineering simulations and Social Engineering Awareness Training can assist your organizations employees in identifying these types of attacks.
Kaiser Permanente data breach exposes health data of 69K people: Kaiser Permanente, one of America’s leading not-for-profit health plans and health care providers, has recently disclosed a data breach that exposed the health information of more than 69,000 individuals. The company revealed in a notice published on its website that an attacker accessed an employee’s email account containing patients’ protected health information on April 5, 2022, without authorization. Sensitive info exposed in the attack includes:
- The patients’ first and last names
- Medical record numbers
- Dates of service
- Laboratory test result information
Design Weakness Discovered in Apple M1 Kernel Protections: Security researchers released details about a new attack they designed against Apple’s M1 processor chip that can undermine a key security feature that protects the operating system kernel from memory corruption attacks. The work offers a tangible example of how the one-two punch of hardware vulnerabilities and low-level software flaws can provide ample opportunities for attackers to run rampant in the kernel.
US military hackers conducting offensive operations in support of Ukraine, says head of Cyber Command: General Nakasone, the head of US Cyber Command, confirmed for the first time that the US was conducting offensive hacking operations in support of Ukraine in response to the Russian invasion. Speaking in Tallinn, Estonia, the general, who is also director of the National Security Agency, told Sky News that he is concerned “Every single day” about the risk of a Russian cyber attack targeting the US and said that the hunt forward activities were an effective way of protecting both America as well as allies.

Microsoft Zero-Day with No Patch!

Overview
CVE-2022-30190, known as Follina, was released by Microsoft on Monday, May 30th, 2022. The vulnerability resides within the Microsoft Support Diagnostics Tool (MSDT), which may allow an attacker to run arbitrary code with the privileges of the calling application. Microsoft Office applications use MSDT to troubleshoot and collect diagnostic information when something goes wrong.

This vulnerability was discovered by the independent cybersecurity researchers at nao_sec after they noticed a strange word document posted to VirusTotal. Using the Remote Template feature in Microsoft Word, an HTML file was pulled from a remote web server. It then made use of the “ms-msdt://” URI scheme to run a malicious payload. Experts are now saying this vulnerability is being exploited by attackers in the wild. Some security researchers have demonstrated execution of the malicious code merely by previewing the document in Windows File Explorer or Outlook.

Exploit
The video below demonstrates how easily this vulnerability can be exploited. Exploit code is now publicly available, making this process trivial. We will outline the steps taken in this video below:

An attacker downloads exploit code from GitHub.
This exploit code is then utilized to create the malicious Word document and stand up a web server to serve up the HTML file. In the video below, this Word document is called “sploit.docx.”
Once the user opens the Word document, you see the MSDT tool also fire off. MSDT is also commonly referred to as “Program Compatibility Troubleshooter.”
The producer of this video then shows you that both a cmd.exe process and powershell.exe process have been launched on the system. At this point, the document can be closed, but the malicious process is still running.
The demo then shows a Cobalt Strike window. Cobalt Strike is a command-and-control framework used for maintaining persistent access on compromised systems. You can see in the video that a “beacon” has been launched on the system. A beacon is an agent on the system that allows an attacker to maintain persistent access and run arbitrary code.
At this point the producer of this video runs “whoami” on the system itself to show you which user account launched the Word document. They then flip back to Cobalt Strike and run “whoami” from the interactive beacon. This displays the same user account. Persistent remote code execution achieved.

What To Do?
At this point in time, Microsoft has not released an official fix for this vulnerability. They are recommending that the MSDT URL protocol be disabled in order to protect systems from this vulnerability. That guidance can be found here. nGuard offers a bevy of services that can help prevent and identify these types of attacks. Both Social Engineering simulations and Social Engineering Awareness Training can assist your organizations employees in identifying these types of attacks. Internal Penetration Testing can boost the overall security posture of your internal network. If a machine on your network does become compromised, you have assurance that the adversary won’t make it very far. Lastly, Managed Event Collection & Correlation gives you 24×7 monitoring from advanced log analysis tools and nGuard professionals who are trained to detect suspicious activity.