Axios is a promise based HTTP client for the browser and Node.js. When Axios starting in version 0.28.0 and prior to versions 0.30.2 and 1.12.0 runs on Node.js and is given a URL with the data: scheme, it does not perform HTTP. Instead, its Node http adapter decodes the entire payload into memory (Buffer/Blob) and returns a synthetic 200 response.

This path ignores maxContentLength / maxBodyLength (which only protect HTTP responses), so an attacker can supply a very large data: URI and cause the process to allocate unbounded memory and crash (DoS), even if the caller requested responseType: 'stream'. Versions 0.30.2 and 1.12.0 contain a patch for the issue.