Article
Active Exploitation of File Transfer Vulnerabilities
Cyber Threats
At Arete
Cybersecurity Trends
Threat actors are actively exploiting two critical vulnerabilities in CrushFTP and Gladinet’s CentreStack and Triofox products, leading to data exfiltration and extortion. CrushFTP, a managed file transfer solution, is vulnerable to an authentication bypass vulnerability designated CVE-2025-31161. The flaw is simple to exploit, and public exploit code is readily available, increasing risk for organizations that use the platform. Meanwhile, Gladinet’s CentreStack and Triofox products, both file-sharing and remote access platforms, are impacted by a critical remote code execution (RCE) vulnerability stemming from a hardcoded key in its configuration. This flaw (CVE-2025-30406) allows attackers to forge payloads and execute arbitrary code on the server.
What’s Notable and Unique
CVE-2025-31161 is a critical vulnerability affecting CrushFTP v10 and v11 and allows unauthenticated attackers to temporarily authenticate as any user, including administrators, leading to full server compromise. Over 1,500 vulnerable instances have been exposed, and as of April 10, 2025, approximately 440 organizations in North America remain vulnerable.
After exploiting the CrushFTP vulnerability, threat actors often install remote monitoring and management (RMM) tools like AnyDesk and MeshAgent before harvesting credentials. When certain threat actors exploit the vulnerability, they also install a Telegram bot to exfiltrate telemetry from infected hosts.
CVE-2025-30406 is a deserialization vulnerability in CentreStack and Triofox caused by the use of a hardcoded or weakly protected ‘machineKey’ in the IIS ‘web.config’ file, which secures ASP.NET ViewState data. If an attacker can obtain or predict this key, they can forge ViewState payloads that pass integrity checks and trigger deserialization, potentially resulting in remote code execution.
Upon successful exploitation, threat actors often deploy a malicious executable, install the MeshCentral remote access tool, and conduct lateral movement within the network. The vulnerable Triofox product is commonly used by managed service providers (MSPs), posing a serious threat to MSPs and their customers.
Analyst Comments
Overlaps in post-exploit techniques of CVE-2025-30406 (CentreStack and Triofox) and CVE-2025-31161 (CrushFTP), indicate potentially coordinated threat activity or shared attacker infrastructure. Threat actors have installed MeshCentral and used IP address 2.58.56[.]16 for post-exploitation communication in incidents after the exploit of both vulnerabilities. However, based on observed behavior and the ease of exploitation, multiple threat actors are likely exploiting these vulnerabilities. At least one threat actor, KillSec, has publicly claimed exploitation and exfiltration by leveraging the CrushFTP vulnerability. Arete has observed other threat actors extort victims after allegedly exploiting the CrushFTP vulnerability.
The CrushFTP vulnerability has been exploited since March 31, 2025, so any organizations using a vulnerable version of CrushFTP that have not updated should assess for potential unauthorized access and exfiltration. Organizations using a vulnerable version of CrushFTP can take two actions to remediate the vulnerability: upgrade to version 10.8.4 or version 11.3.1 or enable a DMZ proxy instance. Applying the patch will not remove the access of any threat actors who have already exploited the vulnerability and created a new valid user account for the application. For organizations affected by the CentreStack and Triofox vulnerability, an updated version was released by the company that resolves the vulnerability and generates a new machine key.
Sources
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CMS Vulnerability Leads to ClickFix Campaign
Threat actors compromised at least 700 education and technology websites in a recent ClickFix campaign by exploiting a critical SQL injection flaw (CVE-2026-26980) in the Ghost content management system (CMS). Adversaries combined the vulnerability with the ClickFix social engineering tactic to steal admin keys and inject a malicious JavaScript that delivers a fake Cloudflare or CAPTCHA verification pop-up, tricking victims into copying and pasting a malicious command into their systems.
What’s Notable and Unique
Rather than targeting the end user first, this campaign is unique in its initial exploitation of the system, followed by social engineering attempts. This hybrid attack style is likely being leveraged to bypass traditional defenses.
This recent campaign also highlights how trusted web properties can be weaponized at scale and coupled with unpatched CMS vulnerabilities. Rather than using the CMS compromise to perpetrate a single attack, threat actors turned it into a supply-chain attack that ultimately affected over 700 trusted websites.
Analyst Comments
As network defenders and their tools enhance threat detection capabilities, adversaries increasingly seek methods to bypass these defenses. By combining vulnerability exploitation, social engineering techniques, and staging for ancillary attacks, this campaign successfully bypassed traditional defenses and inflicted significant impact. Defending against hybrid cyberattacks requires comprehensive security controls beyond simply patching vulnerabilities. Organizations should focus on limiting movement within the environment, detecting abuse of trusted applications, and preventing end-user manipulation.
Sources
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Article
Threat Actors Leverage Fake JPEG Files for Initial Access
In a recent campaign, researchers observed threat actors using fake JPEG image files as a delivery mechanism to initiate the deployment of additional malicious components. The false JPEG files are typically distributed via phishing emails or other social engineering-based lures, and are actually PowerShell-based malware that deploys a trojanized version of ConnectWise ScreenConnect to establish and maintain persistence in the compromised environment.
What’s Notable and Unique
This campaign leverages JPEG images as the initial lure, where the images are not merely decoys but part of the infection workflow. Victims are typically led to download or open an image that triggers hidden execution logic or redirects them to a payload-delivery sequence that initiates later stages of the intrusion chain.
The attack chain is designed to blend into legitimate environments, making detection more difficult. Execution typically relies on scripted or native Windows components, often including PowerShell or other living-off-the-land binaries, enabling fileless or near-fileless execution and reducing forensic artifacts on disk.
The multistage design ensures that the initial JPEG does not directly contain the full payload but instead triggers retrieval or decryption steps that progressively assemble the final malicious components in memory.
Analyst Comments
This campaign illustrates how threat actors continue to blur the line between legitimate file handling and malicious execution chains, indicating potential overlap with remote management or administrative tooling. The use of JPEG-based staging combined with script-based execution reflects a broader evolution toward a stealth-first intrusion design, in which file formats serve as triggers rather than payload containers.
Sources
OPERATION SILENTCANVAS : JPEG BASED MULTISTAGE POWERSHELL INTRUSION
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