# What changed in google-auth-oauthlib

> 4 changes in google-auth-oauthlib 1 from its official release notes, upgrade guides and advisories: 1 breaking, 1 security. Each one cited. Sources checked 2026-10-27. HTML: https://unstale.sh/pypi/google-auth-oauthlib/

To see which of these apply to a repository, run `npx @unstale/cli init` in it.

## google-auth-oauthlib 1

### Breaking changes

- Support for Python 3.9 was dropped, so applications must use a supported Python version. (1.4.0) — [release notes](https://github.com/googleapis/google-cloud-python/releases/tag/google-auth-oauthlib-v1.4.0)

### Security

- Prevents IPv6 address reuse. (1.5.0) — [release notes](https://github.com/googleapis/google-cloud-python/releases/tag/google-auth-oauthlib-v1.5.0)

### Fixes and other changes

- Python 3.15 support is declared, expanding the Python versions developers can use. (1.5.0) — [release notes](https://github.com/googleapis/google-cloud-python/releases/tag/google-auth-oauthlib-v1.5.0)
- Prevents port re-use on Windows. (1.4.1) — [release notes](https://github.com/googleapis/google-cloud-python/releases/tag/google-auth-oauthlib-v1.4.1)