CertyFile: Blockchain-powered and encrypted system to mitigate document forgery

The South Africa-Swiss Bilateral Research Chair in Blockchain Technology aims to explore the advantages and barriers of integrating blockchain technology in supply chain management. Two different focus areas of implementation are envisioned within the import/export of goods in South Africa and Switzerland, namely the agri-food and drugs/medical devices supply chains. The chair also focuses on using blockchain technology to solve real-world problems, with a core developer team that designs, tests and deploys open source blockchain code with an MIT licence, making it freely available for public use. Leading this initiative is Professor Nnamdi Nwulu, the Chairholder of the research chair and a professor of sustainable cyber-physical engineering and blockchain systems.

Document forgery and falsification are acts of presenting false documents or tampering with an existing document to deceive an institution. This act has always been a significant problem for businesses globally. According to a survey by Regula Forensics, 69% of companies identified document forgery as a dominant challenge.[1] A March 2025 report by the US Federal Trade Commission (FTC) pointed out that $12.5 billion was lost to fraud in 2024 alone. Out of these, imposter scams (which always entail document forgery) ranked second, next to investment scams, amounting to $2.95 billion in losses. This represents a 25% increase compared to the previous year.

Additionally, between 2020 and 2024, document falsification related to job applications tripled, with the losses increasing from $90 million in 2020 to $501 million in 2024.[2] Furthermore, false documents are primarily used in identity verification and job applications, exposing organisations to financial loss and reputational risk. All these problems call for a reliable and scalable system that solves the problem of document falsification.

In response to the above mentioned problems, UJ Blockchain launched CertyFile, a blockchain-powered system used for document verification using image processing technologies and AES-256 encryption. To use the system to verify a document, all that is required is for the user/verifier to upload the document, which is then analysed to confirm its authenticity. If the document is genuine, it is verified with the details provided. Otherwise, the user will be informed that no document match exists on the blockchain. This output indicates that the document is possibly fraudulent. This ease of use makes document verification possible on the go without location restrictions. CertyFile is compatible with all major operating systems, including iOS, Android, Windows and web browsers.

Step 1: Open the CertyFile link on your mobile or desktop device.

Step 2: Click the “start” button. The system introduces itself and outlines its functionality to assist with document verification.

Step 3: Upload the document. If it is fake, the system reports that the “document does not match any blockchain record”. If it is valid, it confirms authenticity and provides a link for further verification.

Figure 1: Sample response for a fake document.

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Figure 2: Sample response for a genuine document.

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UJ Blockchain utilises computer vision to analyse QR codes on certificates across various channels, including WhatsApp and Telegram, to which CertyFile is deployed. This gives high accuracy in detecting QR codes from images and detecting fake ones. UJ Blockchain uses its dedicated IPFS gateway with over 2TB bandwidth and 4TB storage, with an encryption layer added, to increase its throughput. This encryption layer offers quick decryption and encryption for different file formats. Also, CertyFile comes with an intelligent system to detect if a document has been edited, making it easy to spot fakes and changed documents.

CertyFile is a robust and scalable system that effectively mitigates document fraud. The system is powered by blockchain technology, giving it immutability, transparency and decentralisation features. These features provide the basis for the stakeholders (such as employers, institutions or regulators) involved in the system to trust the system’s response. Preventing fraudulent documents from slipping through ensures businesses can protect themselves against reputational and financial problems. Moreover, AES-256 encryption ensures user data is secure and shielded, preventing privacy violations.

CertyFile comes with robust security and verification to enhance documentation and can be adopted across different sectors with ease, low-cost usage and deployment, fast verification and easy-to-use systems. It also comes with different channel integration for tools users already know, like WhatsApp and Telegram.

UJ Blockchain keeps training and updating its model to add more features to the system. Upcoming features include:

• Document access controls: This feature allows document owners to grant temporary third-party access with the ability to revoke it anytime.
• Multi-language support: This feature enables the system to communicate with the users in all major South African languages (except sign language). This localised approach improves accessibility and user experience across the country’s diverse population.
• Integration with SSI (Self-Sovereign Identity) frameworks and Verifiable Credentials (W3C standard) for interoperability.

CertyFile is one of several real-world blockchain applications the UJ Blockchain team built. Other projects include (but are not limited to):

• FoodTrolley: Digitising the food parcel collection process for over 10 000 UJ students.
• Thato AI: An AI-powered application offering blockchain education in all South African languages.
• TranzFile: A decentralised, encrypted file-sharing solution for secure and fast document transfer.
• Agri-monitoring systems: Integrating drones, computer vision and blockchain for precision agriculture and remote farmland management.

These innovations highlight UJ Blockchain’s ability to integrate blockchain with other fourth industrial revolution (4IR) technologies such as AI, IOT, computer vision, drone technologies and more. The research chair is open to industrial collaborations to develop real-world solutions, consultations and more.

E-mail UJ Blockchain at blockchain@uj.ac.za or visit blockchain.uj.ac.za to connect or collaborate.