New CTI Labs: CVE-2017-1000353 Offensive and Defensive (October 2025 CISA KEV Additions)
In October 2025, the Cybersecurity and Infrastructure Security Agency (CISA) added five new vulnerabilities to its known exploited vulnerabilities catalogue, one of which was a critical 2017 vulnerability affecting Jenkins versions 2.56 and earlier and 2.46 LTS and earlier. This vulnerability allowed attackers to gain remote code execution on vulnerable instances. Why is this critical for you and your team? Jenkins is a widely used application. Shodan reports confirm that there are 000s of instances exposed to the internet, with the vulnerable versions. With this vulnerability being a critical remote code execution vulnerability, the impact is significant. Understanding how to investigate logs for this attack and understanding how to successfully achieve exploitation is important for any team. Even though it's a 2017 vulnerability, it's a very recent addition to CISA KEV, which illustrates just how significant it is, and that even today, attackers are using this vulnerability to gain footholds and compromise vulnerable victims. Who is the lab for? SOC Analysts Incident Responders Penetration Testers Red Teamers Threat Hunters Here are the links to the labs: Offensive: https://immersivelabs.online/v2/labs/cve-2017-1000353-jenkins-command-injection-offensive Defensive: https://immersivelabs.online/v2/labs/cve-2017-1000353-jenkins-command-injection-defensiveNew Labs - Malterminal: Malware Analysis
With artificial intelligence (AI) and large language models (LLMs) fast becoming a more popular and talked-about set of technologies in every industry in society, it's no surprise that LLM-enabled malware now exists that can dynamically generate code, query data, and offload malicious functionality to LLMs, lowering the barrier of entry for threat actors deploying malware. This lab introduces one of the first known malware samples to ever facilitate the use of LLMs to perform malicious functionality. Why should our customers care? Most, if not all, companies are looking into using AI to varying degrees, whether to make their workforce more efficient and productive or to build full models that facilitate technical processes. With this in mind, and with the advent of basic malware that can use API keys to query LLMs and AI services, we will likely see this particular malware set evolve over time. By doing this lab, you'll begin to see how these pieces of malware are just the stub and querier for AI and how they can be used maliciously. This will showcase what this threat is like in its current state. We shall be monitoring how this threat evolves, so stay tuned for more labs. Who is the defensive lab for? SOC Analysts Incident Responders Threat Hunting Here is a link to the lab: https://immersivelabs.online/v2/labs/malterminal-analysisCVE-2025-53770: Critical Zero-Day RCE Vulnerability in Microsoft SharePoint Servers
An unauthenticated remote code execution (RCE) vulnerability, identified as CVE-2025-53770, has been discovered in on-premise Microsoft SharePoint Servers. This critical zero-day flaw allows attackers to execute arbitrary code on a server without needing to authenticate, posing a significant security risk. The vulnerability has been actively exploited in the wild, with researchers detecting an exploit chain as early as July 18, 2025. What is CVE-2025-53770? The vulnerability stems from insufficient validation of user-supplied data, which can be exploited by a specially crafted request to the server. This allows a remote attacker to execute code with the permissions of the SharePoint application pool, leading to a full compromise of the server – meaning they could have access to sensitive data, install malware, and even have complete control over the system. Which systems are affected? This vulnerability impacts multiple versions of on-premise Microsoft SharePoint servers: SharePoint Server Subscription Edition (Versions earlier than KB5002768) SharePoint Server 2019 (Versions earlier than 16.0.10417.20027/KB5002754) SharePoint Server 2016 (Specific version numbers vary, but generally earlier than the latest security updates) SharePoint Server 2013 and 2010 (While these are end-of-life and no longer supported, Microsoft still lists them as being potentially affected) How could attackers use this vulnerability? Bad actors are actively exploiting CVE-2025-53770 to gain initial access to corporate networks. Since the vulnerability is unauthenticated, attackers can scan the internet for vulnerable SharePoint servers and execute their exploit without needing any user credentials. Once exploited, they can deploy web shells to maintain persistent access, install ransomware, exfiltrate sensitive company data, or use the compromised server as a pivot point to move laterally within the network and attack other systems. The fact that it’s easy to exploit and the high level of access it grants make this a particularly dangerous vulnerability for any organization with an on-premise SharePoint deployment. How to protect your organization To protect your organization from this critical vulnerability, you need to take immediate action: Apply security patches Microsoft has released security updates to address this vulnerability. It’s crucial to apply these patches to all affected SharePoint servers immediately. Hunt for indicators of compromise (IoCs) Since this vulnerability was a zero-day and exploited in the wild, it’s essential to check for signs of a breach. Security teams should analyze SharePoint and web server logs for suspicious requests, particularly those involving unexpected file uploads or unusual processes being executed by the SharePoint application pool identity. Look for newly created .aspx or .ashx files in SharePoint directories that aren’t part of a standard installation. Implement network segmentation Restrict access to your SharePoint servers from the internet as much as possible. If external access is necessary, consider placing the server behind a web application firewall (WAF) with rules designed to block common web attack patterns. Enhance monitoring Increase monitoring of SharePoint servers for any anomalous behavior, such as unexpected outbound network connections, high CPU usage from SharePoint-related processes, or suspicious scheduled tasks being created. Conclusion In conclusion, CVE-2025-53770 represents a severe and immediate threat to organizations utilizing on-premise Microsoft SharePoint Servers. As a critical, unauthenticated remote code execution vulnerability being actively exploited in the wild, it provides a direct gateway for attackers to achieve a full compromise of server integrity, leading to potential data breaches, ransomware deployment, and significant operational disruption. Your response to this threat must be swift and comprehensive. Immediately applying Microsoft’s security patches is a critical first step to prevent exploitation. However, due to its nature as a zero-day exploit, organizations must also assume possible compromise and proactively hunt for IoCs. Strengthening network segmentation and enhancing monitoring are vital secondary measures to protect against this and future threats. Ultimately, a decisive and layered security response is essential to mitigate the substantial risks posed by this vulnerability. Recommended content To learn how to detect and exploit this vulnerability in a sandboxed environment, check out the following labs on the Immersive platform: Defensive: CVE-2025-53770 (ToolShell SharePoint RCE) Offensive: CVE-2025-53770 (ToolShell SharePoint RCE) Share your thoughts Have you seen this vulnerability being exploited in the wild? Have you patched your systems yet? Share your thoughts by commenting in the thread below.New CTI Lab: CVE-2025-9074 (Docker Container Escape): Defensive
Pvotal Technologies published a write-up for a vulnerability in Docker Engine, given a CVSS score of 9.3. CVE-2025-9074 is a flaw in Docker Desktop that exposes the Docker Engine API to any container, with no authentication. Exploitation of this critical vulnerability allows a low-privileged container to issue privileged API commands, take over other containers, and, in some cases, mount the host drive and access files and folders and eventually achieve remote code execution. Why should our customers care? Many organizations rely on containerization in their development teams, and a vulnerability like this could allow an attacker to gain access to any to developer's workstation by mounting a developer's host drive. The possibility of supply chain attacks is increased due to malicious containers that can be used by developers, which can have start-up scripts that mount and "escape" the containerized environment. Who is the defensive lab for? System Administrators Developers SOC Analysts Incident Responders Threat Hunting Here are the links to the labs: Defensive: https://immersivelabs.online/labs/cve-2025-9074-docker-container-escape-defensiveImmersiveOne: Scattered Spider Release
Scattered Spider has continuously been a threat to many of our customers, and one of the reasons is that they have techniques and tactics that can affect all members of an organization. From their advanced social engineering tactics targeting less security-focused users in an organization to bypassing defences long enough to deploy ransomware and steal data from some of the largest organizations in the world. Therefore, Immersive is releasing an ImmersiveOne approach to protecting our customers. This means customers now have access to the following: Lab – Scattered Spider and Dragonforce: Campaign Analysis Lab – Threat Actors: Scattered Spider Workforce Scenario – Social Engineering Techniques Crisis Sim – Responding to a Scattered Spider Attack The technical and non-technical labs, workforce scenario, and Crisis Sim scenario release will enable everyone inside an organization to prepare and be ready for threats posed by Scattered Spider. For an in-depth blog on Scattered Spider and what to think about in a crisis, follow the link here: https://www.immersivelabs.com/resources/blog/scattered-spider-what-these-breaches-reveal-about-crisis-leadership-under-pressureCVE-2025-53770 - Unauthenticated Remote Code Execution via unsafe deserialization in Microsoft SharePoint Server
Understanding the RCE On July 22, 2025, Immersive’s threat research team was trying to understand how the SharePoint zero-day vulnerability was uncovered, based on Eye Security’s initial article. There were many proofs of concept (PoCs) and initial articles on indicators of attack (IoAs) and their severity. But none covered the exploit itself or could help us understand how the exploit was weaponized in depth. In this blog, I’ll share our research process and how we (eventually!) got to the bottom of this exploit. The challenges of building a CTI lab Our initial thought process for building this Cyber Threat Intelligence (CTI) lab was fairly straightforward. We’d understand the indicators of compromise (IoCs) and the PoCs that were shared in the article, try replicating it with the PoC, and obtain some logs. However, it was easier said than done. What went wrong? The PoCs just didn't work, and there was no way for us to understand why. This makes sense retrospectively – initial articles only provided surface-level information, rather than details on how the exploit was made. We ended up deploying different variants of SharePoint to see which were vulnerable. Alas, nothing worked (I’ll explain why this happened in more depth later on). Looking at the logs to identify the problem didn’t work either, because who looks at logs, right? Some of the initial PoCs were taken down, and the ones remaining were missing a piece of the puzzle. It was also fairly noticeable that many of the PoCs added to GitHub weren’t true either, and some were ransomware binaries! Dissecting the payload – mistakes and a learning curve Based on the initial brief from the Eye Security article, we figured out that it was a deserialization problem. After many days of unravelling and building multiple SharePoint servers with different versions, the “Hallelujah” moment finally arrived. A new remote code execution (RCE) module for this exploit was committed to Metasploit's GitHub repo. It wasn't the code that mattered much to us, but the comments in it that got us interested: The highlighted comments helped us map out which deserialization gadget chain works against specific SharePoint Server versions. This was important, as the exploit itself abuses insecure deserialization in the ViewState on SharePoint pages like ToolPane.aspx. This is when it hit us: our initial exploit of the RCE using the TypeConfuseDelegate gadget with BinaryFormatter wasn't working because we weren’t targeting the versions that were vulnerable to that gadget chain. To put this to the test, we had the right version built (v16.0.10337.12109) and also decided to further analyze the payload itself from the Metasploit module – I know it's cutting corners, but I was very keen on how it all works together! To achieve this, we downloaded the earliest exploit module commit on its GitHub, added it to our existing Metasploit framework, and intercepted the request using BurpSuite. This gave us the PoC, which we could analyze: Obviously, there was no need to reinvent the wheel since Metasploit already had a functional module, but where’s the fun in that? Dissecting the payload – decoding It’s already noticeable that the payload is URL-encoded. By decoding it, you’ll be able to see the body of the request. It has references to controltemplates/ACLEditor and an Excel DataSet, which is commonly used in .NET deserialization exploits, along with a Base64 encoded and compressed data table: The next step was to extract and Base64 decode the compressed data table: The decoded and decompressed information is the raw XML schema and DiffGram that the DataSetWrapper spits out. The part highlighted in the red box is the embedded first-stage gadget, Base64 encoded as an XSD string. Remember when I mentioned that our PoCs weren't working earlier? It’s because we didn't embed our Base64 encoded payload onto a raw XML schema and DiffGram. If you take the Base64 encoded XSD string and decode it, you’d get the payload. The payload I had on Metasploit was: And by decoding the string obtained from above, we can see it too: Weaponizing our PoC to emulate the IoCs With all the juicy information to hand, it was time to recreate this and see how threat actors in the wild did it. Bear in mind that the IoCs from the research article mentioned they weren’t obtaining any shells from the RCE, but stealthily leaking cryptographic secrets from SharePoint servers, which were chained to craft a fully valid and signed payload using ysoserial. The PoC implemented based on the work from the Metasploit module wraps our initial “inner” ysoserial payload inside an XML and DataSet gadget that SharePoint expects, then serializes, compresses, and Base64 encodes it. The payload that was built closely resembles what’s seen in the wild, which was dropping malicious content to a file named spinstall0.aspx that leaks cryptographic secrets. This Base64 payload was then embedded into an XML and DataSet gadget, using our PoC: All that remained was to send the payload. Here’s what we noticed upon sending the request via Burp: And while looking at the Process Explorer running on our SharePoint test environment: Similar to the IoCs, you’ll note that w3wp.exe spawns cmd.exe, and a PowerShell process is then spawned from the cmd.exe child process. If it’s succeeded, you should be able to navigate to https://X.X.X.X/_layouts/15/spinstall0.aspx to view and read the SharePoint’s MachineKey config file, including the ValidationKey: Finally, from our ELK logs: As you’ll notice, the log shows that the exploit’s PowerShell payload used set-content to write an ASPX backdoor into SharePoint’s _layouts directory (spinstall0.aspx). In summary Looking back at this exploit, it’s interesting from an offensive perspective to see how advanced persistent threat actors are finding creative ways to compromise organization infrastructures. In the meantime, I can only send prayers to the SOC analysts and Sysadmins fixing SharePoint, because let’s be honest – SharePoint is a cave nobody comes out alive from! For more information and finer details on how the exploit works, I'll leave this fantastic article here: Viettel Cyber Security: SharePoint ToolShell – One Request PreAuth RCE ChainNew CTI Labs: CVE-2025-53770 (ToolShell SharePoint RCE): Offensive and Defensive
Recently, a critical zero-day vulnerability affecting on-premise SharePoint servers, identified as CVE-2025-53770, was uncovered. This vulnerability allows for authentication bypass, leading to remote code execution, and has been actively exploited in the wild. Eye Security researchers detected an in-the-wild exploit chain on July 18, 2025, during an incident response engagement. This discovery led to Microsoft assigning two CVEs: CVE-2025-53770 and CVE-2025-53771. The attack notably leveraged a combination of vulnerabilities to achieve its objectives, impacting numerous SharePoint servers globally. There is now a public exploit available for anyone wanting to achieve remote code execution. Why should our customers care? This critical vulnerability has been added to the CISA Kev Catalog. and with no authentication or user interaction, a vulnerable SharePoint server can be fully taken over remotely, letting attackers run arbitrary code as if they were privileged admins. SharePoint is a complex and large system that often holds a lot of sensitive data for organizations and is often a targeted system for attackers. Who is the defensive lab for? System Administrators SOC Analysts Incident Responders Threat Hunters Who is the offensive lab for? Red teamers Penetration Testers Threat Hunters Here are the links to the labs: Offensive: https://immersivelabs.online/v2/labs/cve-2025-53770-toolshell-sharepoint-rce-offensive Defensive: https://immersivelabs.online/v2/labs/cve-2025-53770-toolshell-sharepoint-rce-defensiveNew CTI Lab: CVE-2025-32463 (Sudo Chroot Elevation of Privilege): Offensive
On June 30, 2025, the Stratascale Cyber Research Unit (CRU) team identified a critical local privilege escalation vulnerability in sudo, tracked as CVE-2025-32463. This vulnerability, related to sudo's chroot option, can allow an attacker to escalate privileges to root on an affected system. Why should our customers care? This critical vulnerability is reasonably trivial to exploit, and should an attacker gain user-level access to a vulnerable machine, they'll be able to elevate their privileges and have full control over the machine. It has come to our attention that not many people are aware that sudo has versioning. It is a binary that is constantly iterated upon, which naturally may introduce new vulnerabilities. If administrators and security analysts are not aware of how these vulnerabilities work, this can lead to significant risks and impacts. Who is it for? Red Teamers Penetration Testers System Administrators Here is a link to the lab: https://iml.immersivelabs.online/labs/cve-2025-32463-sudo-chroot-elevation-of-privilege-offensiveNew CTI/OT Lab: Norwegian Dam Compromise: Campaign Analysis
We have received reports of a cyber incident that occurred at the Lake Risevatnet Dam, near Svelgen, Norway, in April 2025. A threat actor gained unauthorized access to a web-accessible Human-Machine Interface (HMI) and fully opened a water valve at the facility. This resulted in an excess discharge of 497 liters per second above the mandated minimum water flow. Which persisted for four hours before detection. This attack highlights a dangerous reality: critical OT systems are increasingly exposed to the internet, making them accessible to threat actors. In this case, control over a dam’s valve system was obtained via an insecure web interface, a scenario that could have had even more severe consequences. A recent report by Censys identified over 400 exposed web-based interfaces across U.S. water utilities alone. This dam incident in Norway exemplifies the tangible risks posed by such exposures. In this lab, you will be taken through the attack from an offensive viewpoint, including cracking an HMI and fully opening two valves. Why should our customers care? OT environments, including dams, energy grids, and oil pipelines, are foundational to national security and daily life. These systems cannot be secured using traditional IT playbooks. As OT becomes more connected, tailored security strategies are critical to prevent unauthorized access and catastrophic failures. Who is it for? Incident responders SOC analyst Threat Hunters Red Teamer Penetration Testers OT Engineers Here is the link to the lab: https://immersivelabs.online/v2/labs/norwegian-dam-compromise-campaign-analysisNew CTI Lab: CVE-2025-33073 (SMB Elevation of Privilege): Defensive
Another vulnerability patched was released during Microsoft's June 2025 patch Tuesday review! An important elevation of privilege vulnerability was listed, and if exploited successfully, attackers can achieve elevation of privilege on the compromised machine. Even though it's not recorded to have been exploited in the wild as yet, the fact that research exists with details on how the vulnerability was found improves the chances an attacker will attempt to exploit this flaw against a victim.In these labs, you will be taken through the vulnerability from both an offensive and defensive perspective. Why should our customers care? This is a new vulnerability that has just been patched, and is has in depth research released about it. Successful exploitation of this vulnerability allows attackers to elevate their privileges and achieve command execution on a victim machine. Learn what sort of indicators this exploit leaves, but also learn how to execute and take advantage of this vulnerability! Who is it for? Incident responders SOC analyst Threat Hunters Red Teamer Penetration Testers Here is the link to the labs: Defensive: https://immersivelabs.com/v2/labs/cve-2025-33073-smb-elevation-of-privilege-defensive Offensive: https://immersivelabs.com/v2/labs/cve-2025-33073-smb-elevation-of-privilege-offensive Container 7 Release We have released a threat detection for this particular vulnerability, helping the community to protect against any potential use of this vulnerability. https://github.com/Immersive-Labs-Sec/SigmaRules/blob/main/cve-2025-33073-smb-exploit.yml
