Your AI API key is not a password. It is a credit card with no spending limit. That is the lesson from Railway, the app-hosting platform, which disclosed that an October breach exposed stored environment variables across up to 100,000 workspaces, roughly 1.85% of the total.
According to The Hacker News, attackers pulled AI provider keys from those variables and ran up an estimated $740,000 in unauthorized usage. Railway says it will pay those charges itself if the AI providers will not issue refunds. The company also reported that tokens linked to 1,852 users were accessed, along with stored build histories and its internal code repository.
How it happened
Per the report, the attacker used an unknown filesystem isolation flaw in the build system, then a misconfigured identity binding to obtain cloud credentials, and finally decrypted customer variables. Refund policies differ by provider: AWS Bedrock and Google Gemini are refunding under fraud policies, while OpenAI reviews claims case by case.
Timing is everything: the best moment to rotate your keys was before the breach. The second best is today.
What to do this week
- Rotate any AI or cloud keys stored in hosted environment variables.
- Set hard monthly spend caps and alerts with every AI provider.
- Use separate, scoped keys per project so one leak does not drain everything.
For anyone building side projects or working in a startup, this is career-relevant hygiene. Shipping fast with AI tools is great, but the person who notices a runaway bill first is the one who keeps their job and their savings.
