Seth Godin wrote an article about a surprisingly common vulnerability: programmers leaving authentication credentials and other secrets in publicly accessible software code:

Researchers from security firm GitGuardian this week reported finding almost 4,000 unique secrets stashed inside a total of 450,000 projects submitted to PyPI, the official code repository for the Python programming language. Nearly 3,000 projects contained at least one unique secret. Many secrets were leaked more than once, bringing the total number of exposed secrets to almost 57,000.

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The credentials exposed provided access to a range of resources, including Microsoft Active Directory servers that provision and manage accounts in enterprise networks, OAuth servers allowing single sign-on, SSH servers, and third-party services for customer communications and cryptocurrencies. Examples included:

• Azure Active Directory API Keys
• GitHub OAuth App Keys
• Database credentials for providers such as MongoDB, MySQL, and PostgreSQL
• Dropbox Key
• Auth0 Keys
• SSH Credentials
• Coinbase Credentials
• Twilio Master Credentials.