A collaboration between Google’s research unit and a Dutch institute on Thursday cracked a widely used cryptographic technology that has been one of the key building blocks of Internet security.
The algorithm, known as Secure Hash Algorithm 1 or SHA-1, is currently used to verify the integrity of digital files and signatures that secure credit card transactions as well as Git open-source software repositories.
Researchers were able to demonstrate a “collision attack” using two different PDF files with the same SHA-1 fingerprint, but with different visible content, according to a paper published by Amsterdam-based Centrum Wiskunde & Informatica.
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“Moving forward, it’s more urgent than ever for security practitioners to migrate to safer cryptographic hashes such as SHA-256 and SHA-3,” according to a post by the collaborators on Google’s security blog.