A Swiss AI model succeeds in bypassing Google’s reCAPTCHA
A Swiss AI model succeeds in bypassing Google’s reCAPTCHA


Recently, a team of researchers from theETH Zurich in Switzerland made a splash by modifying an existing AI model to successfully solve the human testing system reCAPTCHA from Google. This development raises important questions regarding online security and the effectiveness of CAPTCHA systems.
An innovative team
Andreas Plesner, Tobias Vontobel and Roger Wattenhofer have developed a model based on the famous tool You Only Look Once (YOLO)recognized for its effectiveness in image processing. Their research, available on the preprint server arXivdemonstrates how a minor adjustment to an existing model can significantly improve its performance.
The role of CAPTCHAs in web security
For decades, website administrators have used a variety of techniques to protect their resources from malicious bots. Among these methods, the Fully automated public Turing testcommonly called CAPTCHA, is essential. Through this system, users must complete specific tasks, such as clicking images, to prove that they are not robots.
In 2007Google has implemented its own version: the reCAPTCHA v2. This system was designed to enhance security while providing a relatively smooth user experience. Users must recognize and select specific visual elements, which can pose considerable challenges for automated systems.
Remarkable technical progress
The research carried out by the Swiss team demonstrates that it is possible to adapt an AI model with little effort to bypass reCAPTCHA. The researchers focused their work on typical objects encountered in reCAPTCHA challenges, including:
- Cars
- Bridges
- Traffic lights
By training the model on thousands of photos of these objects, they showed that the model did not need absolute precision. CAPTCHA systems, including reCAPTCHA, allow for multiple attempts, which has proven to be beneficial for their model.
Test results indicate that although the model fails on some images, it often succeeds in correcting its approach on further attempts. Additionally, the researchers noted that only 13 categories of objects were enough to effectively train the model to solve reCAPTCHA puzzles.
Challenges to overcome

Extensive testing revealed that this model could even fool more sophisticated versions of CAPTCHA, incorporating things like mouse tracking or browser history. This discovery paves the way for additional research aimed at designing more robust CAPTCHA systems capable of resisting attacks carried out by AI models.
Futuristic implications
The work carried out by this team of researchers not only illustrates innovation in the field of AI, but also raises concerns about the future of online security systems. As technology continues to evolve, there is an urgent need to rethink digital identity verification methods.
It seems that the race between CAPTCHA system developers and artificial intelligence researchers is only just beginning. As these advances continue, it will be crucial to adopt more sophisticated strategies to ensure internet security.
In conclusion
The Swiss team’s results reveal an alarming and fascinating potential for interactions between artificial intelligence and online security systems. The need for constant innovation in the field of CAPTCHAs is undeniable, as is the need for regular updating of security protocols.
More information: Andreas Plesner et al, Breaking reCAPTCHAv2, arXiv (2024). DOI: 10.48550/arxiv.2409.08831






