> For the complete documentation index, see [llms.txt](https://devise-token-auth.gitbook.io/devise-token-auth/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://devise-token-auth.gitbook.io/devise-token-auth/security.md).

# Security

This gem takes the following steps to ensure security.

This gem uses auth tokens that are:

* [changed after every request](/devise-token-auth/conceptual.md#about-token-management) (can be [turned off](https://devise-token-auth.gitbook.io/devise-token-auth/config/initialization)),
* [of cryptographic strength](https://ruby-doc.org/stdlib-2.1.0/libdoc/securerandom/rdoc/SecureRandom.html),
* hashed using [BCrypt](https://github.com/codahale/bcrypt-ruby) (not stored in plain-text),
* securely compared (to protect against timing attacks),
* invalidated after 2 weeks (thus requiring users to login again)

These measures were inspired by [this stackoverflow post](https://stackoverflow.com/questions/18605294/is-devises-token-authenticatable-secure).

This gem further mitigates timing attacks by using [this technique](https://gist.github.com/josevalim/fb706b1e933ef01e4fb6).

But the most important step is to use HTTPS. You are on the hook for that.


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