Cognito - Sub attribute seems to be no more a valid Uuid

Question

Until now, I was thinking the generated value for the sub attribute of congito user was a valid UUID (typically v4).

But the users I've generated for my tests (I also generated new user pools for my tests), the sub always value contains a 7 as the first digit of the third group ex: 
*62e51434-50a1-7070-842a-82a33ec1174f
62e53484-a0a1-70c7-4c6b-c90380fc8519*

Is the cognito user sub attribute a valid UUID ?

Answer

Finally, I didn't manage to get a new pool that generate Uuid v7. It seems the issue was limited in time. 
Maybe a problem shadow solved by AWS team ;)

Answer

Hi, version 7 is a new uuid format.

See https://www.ietf.org/archive/id/draft-peabody-dispatch-new-uuid-format-04.html#name-uuid-version-7

```
UUID version 7 features a time-ordered value field derived from the widely implemented and 
well known Unix Epoch timestamp source, the number of milliseconds seconds since midnight 
1 Jan 1970 UTC, leap seconds excluded. As well as improved entropy characteristics over 
versions 1 or 6.
```

Cognito - Sub attribute seems to be no more a valid Uuid

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