Cybersecurity analysts are raising concerns about a growing trend in which corporate cloud-based file-sharing platforms are being leveraged to extract sensitive organizational data. A cybercrime actor known online as “Zestix” has recently been observed advertising stolen corporate information that allegedly originates from enterprise deployments of widely used cloud file-sharing solutions.
Findings shared by cyber threat intelligence firm Hudson Rock suggest that the initial compromise may not stem from vulnerabilities in the platforms themselves, but rather from infected employee devices. In several cases examined by researchers, login credentials linked to corporate cloud accounts were traced back to information-stealing malware operating on users’ systems.
These malware strains are typically delivered through deceptive online tactics, including malicious advertising and fake system prompts designed to trick users into interacting with harmful content. Once active, such malware can silently harvest stored browser data, saved passwords, personal details, and financial information, creating long-term access risks.
When attackers obtain valid credentials and the associated cloud service account does not enforce multi-factor authentication, unauthorized access becomes significantly easier. Without this added layer of verification, threat actors can enter corporate environments using legitimate login details without immediately triggering security alarms.
Hudson Rock also reported that some of the compromised credentials identified during its investigation had been present in criminal repositories for extended periods. This suggests lapses in routine password management practices, such as timely credential rotation or session invalidation after suspected exposure.
Researchers describe Zestix as operating in the role of an initial access broker, meaning the actor focuses on selling entry points into corporate systems rather than directly exploiting them. The access being offered reportedly involves cloud file-sharing environments used across a range of industries, including transportation, healthcare, utilities, telecommunications, legal services, and public-sector operations.
To validate its findings, Hudson Rock analyzed malware-derived credential logs and correlated them with publicly accessible metadata and open-source intelligence. Through this process, the firm identified multiple instances where employee credentials associated with cloud file-sharing platforms appeared in confirmed malware records. However, the researchers emphasized that these findings do not constitute public confirmation of data breaches, as affected organizations have not formally disclosed incidents linked to the activity.
The data allegedly being marketed spans a wide spectrum of corporate and operational material, including technical documentation, internal business files, customer information, infrastructure layouts, and contractual records. Exposure of such data could lead to regulatory consequences, reputational harm, and increased risks related to privacy, security, and competitive intelligence.
Beyond the specific cases examined, researchers warn that this activity reflects a broader structural issue. Threat intelligence data indicates that credential-stealing infections remain widespread across corporate environments, reinforcing the need for stronger endpoint security, consistent use of multi-factor authentication, and proactive credential hygiene.
Hudson Rock stated that relevant cloud service providers have been informed of the verified exposures to enable appropriate mitigation measures.
Apparently, the incident took place on May 3, targeting primarily the third-party vendor. No impact on the airlines’ own network or systems has been reported.
On April 30, the threat actor gained unauthorized access to the Pilot Credentials’ systems and stole files comprising data supplied by a few candidates in the pilot and cadet recruiting process.
According to the official information shared with Maine’s Office of the Attorney General, the breach impacted 5745 pilots and applicants of American Airlines, whereas Southwest reported that around 3009 individuals’ information was compromised.
"Our investigation determined that the data involved contained some of your personal information, such as your name and Social Security number, driver’s license number, passport number, date of birth, Airman Certificate number, and other government-issued identification number(s)," says the American Airline.
The airlines will now drive all pilot and cadet candidates to self-managed internal portals, even though there is no proof that the pilots' personal information was intentionally targeted or exploited for fraudulent or identity theft purposes.
"We are no longer utilizing the vendor, and, moving forward, Pilot applicants are being directed to an internal portal managed by Southwest," Southwest Airlines stated. Both Airlines further notified law enforcement pertaining to its authorities in case of data breaches and are cooperating with the ongoing investigation of the issue.
Another case of a data breach that came to light was when American Airlines was targeted back in September 2022. This breach impacted around 1,708 customers and airline employees.
Prior to this, the airline was a victim of a phishing attack that resulted in the compromise of the email accounts of numerous of its employees. The breach included employees’ and customers’ credentials like their names, dates of birth, mailing addresses, phone numbers, email addresses, driver's license numbers, passport numbers, and/or certain medical information.
Further investigation on the matter indicated that the threat actors involved in these breaches may as well have utilized the employees’ compromised accounts to launch more phishing attacks.
The Sophos 2022 Threat Report, released by Sophos, a pioneer in next-generation cybersecurity, illustrates how the gravitational influence of ransomware is attracting other cyber threats to building one vast, linked ransomware delivery system, having essential ramifications for IT security.
Entry-level hackers can buy malware and spyware installation tools from illicit markets like Genesis, and also sell illegal passwords or other data in mass. Access brokers increasingly sell other criminal groups' credentials and susceptible software exploits.
A new ransomware-as-a-service economy has emerged in the last decade due to the rising popularity of ransomware. In 2022, this as-a-service business model has grown, and almost every component of the cybercrime toolkit from initial infection to methods of evading detection is now accessible for purchase, according to the researchers.
Several step-by-step tools and methods that attackers might use to spread the ransomware were revealed when an affiliate of the Conti ransomware published the deployment guide supplied by the operators. RaaS affiliates and other ransomware operators can use malware distribution platforms and IABs to discover and target potential victims once they have the virus they require. The second significant trend predicted by Sophos is being fueled by this.
Gootloader was launching innovative hybrid operations in 2021, as per Sophos's research, that blended broad campaigns with rigorous screening to identify targets for particular malware packs.
Ransomware distribution and delivery will continue to be adapted by well-known cyber threats. Which include spam, spyware, loaders, droppers, and other common malware in addition to increasingly sophisticated, manually handled first access brokers.
Data theft and exposure, threatening phone calls, distributed denial of service (DDoS) assaults, and other pressure tactics were all included in the list of ten pressure methods Sophos incident responders compiled in 2021.
Cryptocurrency will continue to feed cybercrimes like ransomware and unlawful crypto mining. In 2021, Sophos researchers discovered crypto miners like Lemon Duck and MrbMiner, which installed themselves on machines and servers by using newly revealed vulnerabilities and targets that had already been compromised by ransomware operators. Sophos anticipates that the trend will continue until international cryptocurrencies are better regulated.
In addition to promoting their products, cybercrime vendors sometimes post job openings to hire attackers with specialized capabilities. In addition to profiles of their abilities and qualifications, job seekers are posting help-wanted sites on some markets, which also have technical hiring personnel.
As web services grow, different kinds of credentials, particularly cookies, can be utilized in a variety of ways to penetrate networks more deeply and even get through MFA. Credential theft continues to be one of the simplest ways for new criminals to enter gray markets and start their careers.