Base64 itself is not harmful, its presence may hide sensitive or unexpected information—such as secrets, tokens, or entire documents—that bypasses regular log filters or monitoring tools.
Base64 content in logs may indicate attempts to obfuscate data, misuse of the system, or improper data handling. It can also lead to compliance issues if sensitive content is being stored without proper controls.
An internal user sends a prompt to an AI model containing a Base64-encoded file for processing. The full encoded string is logged by the system. Later, security teams discover the string contains a decoded PDF with customer financial data, unintentionally exposing confidential information in the logs. This creates both a security risk and a compliance violation.
