CBA, Westpac turn to ‘Daybreak’, OpenAI’s powerful GPT-5.5-Cyber to test cybersecurity defences
Australian Financial Review
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Details
- Date Published
- 19 May 2026
- Priority Score
- 5
- Australian
- Yes
- Created
- 20 May 2026, 02:00 am
Description
They are utilising the artificial-intelligence giant’s most powerful model to test for vulnerabilities, while rival Anthropic engages with the RBA.
Summary
Major Australian financial institutions are deploying frontier AI models like OpenAI’s GPT-5.5-Cyber to proactively identify and red-team vulnerabilities within critical national infrastructure. The use of these advanced capabilities represents a shift in defensive AI posture, highlighting the dual-use nature of frontier models that can both secure and potentially compromise large-scale financial systems. The strategic engagement of Anthropic with the Reserve Bank of Australia further underscores the growing intersection between catastrophic risk management, national security, and sovereign AI governance within the Australian banking sector.
Body
CompaniesFinancial ServicesCybersecurityPrint articleJames EyersSenior ReporterUpdated May 20, 2026 – 7.23am, first published at 5.00amMajor Australian banks are using OpenAI’s most powerful artificial intelligence model to test for vulnerabilities in their cybersecurity systems, while rival Anthropic plans to brief the Reserve Bank of Australia on the ability of its Mythos program to identify threats in the financial system and critical infrastructure.Commonwealth Bank and Westpac have turned to the OpenAI model – known as GPT-5.5-Cyber – after Anthropic restricted access to Mythos to a group of US technology companies.Loading...SaveLog in or Subscribe to save articleShareCopy linkCopiedEmailLinkedInTwitterFacebookCopy linkCopiedShare via...Gift this articleSubscribe to gift this articleGift 5 articles to anyone you choose each month when you subscribe.Subscribe nowAlready a subscriber? LoginLicense articleFollow the topics, people and companies that matter to you.Find out moreRead MoreCybersecurityBig fourRBAAIAnthropicOpenAIAPRASubscriber exclusiveFetching latest articles