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Ransomware Trends & Data Insights: December 2025
Arete Analysis
Consistent with the second half of 2025, Akira continues to dominate the ransomware landscape. In December, the group was responsible for over a third of all ransomware and extortion engagements observed by Arete. Akira was also responsible for 10% more ransomware attacks than second and third most active groups, Qilin and INC Ransom, combined. Collectively, the top three most active threat groups in December comprised about 57% of all activity Arete observed during the month.
Figure 1. Activity from the top 3 threat groups in December 2025
Throughout the month of December, analysts at Arete identified several distinct trends behind the threat actors perpetrating cybercrime activities:
In addition to Akira, Qilin, and INC, there has recently been an uptick in engagements attributed to RansomHouse, a group that Arete had not observed since early 2024. Reporting from December 2025 indicated that the group updated its encryption code to make it more efficient, which could partly explain the increase in RansomHouse engagements observed in November and December.
In early December, a maximum-severity flaw was reported in the widely used JavaScript library React that allows unauthenticated remote attackers to execute malicious code on vulnerable instances. The vulnerability, tracked as CVE-2025-55182, also known as React2Shell, was assigned a maximum CVSS severity rating of 10.0, with an estimated 39% of cloud environments affected at the time the vulnerability was disclosed. Organizations should prioritize immediate patching to address the React2Shell (CVE-2025-55182) vulnerability and ensure all internet-facing applications are updated to the vendor-recommended versions.
In late December 2025, a high-severity, pre-authentication memory vulnerability was disclosed that affects MongoDB versions 3.6 and later. Referred to as MongoBleed (CVE-2025-14847), the vulnerability enables unauthenticated attackers to send malformed network messages, thereby leaking uninitialized server memory that contains sensitive data, such as credentials, tokens, and API keys. While the flaw does not allow for remote code execution and no ransomware campaigns have been confirmed, researchers have linked it to real-world abuse, including a suspected Ubisoft Rainbow Six Siege backend compromise. Data leaked from these incidents could enable follow-on attacks, including ransomware. Organizations with publicly exposed MongoDB servers affected by the vulnerability should immediately patch to the latest version.
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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.
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700+ education and tech websites hijacked in huge ClickFix malware campaign
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Ghost CMS Vulnerability Exploited to Infect 700 Sites With ClickFix Malware
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.
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OPERATION SILENTCANVAS : JPEG BASED MULTISTAGE POWERSHELL INTRUSION
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