The FBI Denver Field Office has warned about a growing scam involving free online file converter tools, which appears to be a significant cybersecurity concern. These tools, while converting files as advertised, often distribute malware, leading to serious issues like ransomware and identity theft, affecting users across the region.
Online File Converter Scam Warning by FBI Denver
On March 7, 2025, the FBI Denver Field Office released a statement warning the public about a scam involving free online document converter tools. These tools, while converting files as advertised, often distribute malware, leading to serious issues like ransomware and identity theft, affecting users across the region. The FBI Denver also has highlighted that this is not a localized issue, but rather a global scheme orchestrated by cybercriminals worldwide. The agency has observed a noticeable increase in the number of these deceptive free online converters, signifying a growing trend in this type of cyberattack.
The methods employed by these cybercriminals involve offering seemingly legitimate free file conversion services that, in reality, deliver malicious software or exfiltrate uploaded information such as Social Security numbers, financial credentials, and cryptocurrency details. Cybercriminals creating fake online file converter websites that closely resemble legitimate tools.
These deceptive sites often mimic the appearance and functionality of popular platforms used for converting common file formats such as .pdf, .doc, and .jpg. They may also offer services such as combining multiple files into one, for instance, merging several .jpg images into a single .pdf document. Furthermore, some fraudulent sites masquerade as tools for downloading MP3 or MP4 media files from various online sources.
By employing sophisticated URL manipulation tactics and potentially paying for search engine advertisements, these fraudulent sites can appear at the top of search results, making them highly visible to users actively searching for online file conversion tools. Overall, this is a common tactic, with ads in google search results serving as a vector for the spread of malware.
How does the malware scheme operate?
The primary method by which these fake online file converters compromise users’ systems is by embedding malware within the converted file that the user subsequently downloads. Alarmingly, many of these fraudulent converters actually perform the advertised file conversion, leading victims to believe that the process was successful and legitimate. This functional aspect of the scam makes it pretty convincing, as users are less likely to suspect malicious activity if they receive the expected converted file.
In some instances, the cybercriminals may employ a slightly different tactic, encouraging users to download a separate software tool or a browser extension to facilitate the file conversion process. These seemingly helpful downloads, however, are often the vehicles through which malware is installed on the victim’s device.
Recent research suggests that the malware involved is often a loader-type malware, such as Gootloader, which is a JScript-based malware family leveraging SEO poisoning. Gootloader typically lures victims into downloading a ZIP archive that poses as a document, containing a JavaScript file. When executed, this file connects to a command and control server to download additional malware, such as infostealers or ransomware.
Another prevalent technique used by these fake converters is “scraping” the files that users upload for conversion. This involves the malicious website directly extracting personal information from the submitted files, such as Social Security numbers, passwords, and banking or cryptocurrency details, without necessarily relying on persistent malware installation.
This dual approach, combining malware installation with direct data theft, maximizes the potential for harm and financial gain for the attackers. The exploitation of search engine rankings further increases the chances of users encountering these malicious sites in the first place.
While the official FBI warning might not explicitly name specific malicious websites, as of now, some researchers have reported on examples. These examples include:
- Imageconvertors[.]com
- convertitoremp3[.]it
- convertisseurs-pdf[.]com
- convertscloud[.]com
- convertix-api[.]xyz
- convertallfiles[.]com
- freejpgtopdfconverter[.]com
- primeconvertapp[.]com
- 9convert[.]com
These are just a few sites, most of which are already non-functional. However, if you come across a suspicious site and doubt whether it is malicious or not, you can use our free URL scanner.
How to protect yourself?
While the use of the above methods is nothing new, we are now seeing a continuing trend of attackers using search advertising. Looking ahead, these deceptive tactics will continue to evolve. We can anticipate seeing more sophisticated methods of social engineering, involving artificial intelligence.
For users, the best approach is to cultivate a mindset of caution and skepticism. Prioritize using reputable software (not cracked) installed directly on your computer or well-known online services from trusted providers. Remember that if a service seems too good to be true, it probably is, and the convenience of a free online file converter might come at a significant cost to your security and privacy.
Given the nature of these threats, users should also consider enabling two-factor authentication for added security and regularly updating all software to patch vulnerabilities. A strong recommendation is to use anti-malware software like GridinSoft Anti-Malware, which excels at detecting and removing threats. Its Internet Security module and real-time protection provide protection against these file converter scams.p>
