Version identification: xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx
The four-bit M and the 1- to 3-bit N fields code the format of the UUID itself.
| Version | Notes |
|---|---|
| 0 | Only 00000000-0000-0000-0000-000000000000 |
| 1 | based on time, or clock sequence |
| 2 | reserved in the RFC 4122, but ommitted in many implementations |
| 3 | based on a MD5 hash |
| 4 | randomly generated |
| 5 | based on a SHA1 hash |
- intruder-io/guidtool - A tool to inspect and attack version 1 GUIDs
$ guidtool -i 95f6e264-bb00-11ec-8833-00155d01ef00 UUID version: 1 UUID time: 2022-04-13 08:06:13.202186 UUID timestamp: 138691299732021860 UUID node: 91754721024 UUID MAC address: 00:15:5d:01:ef:00 UUID clock sequence: 2099 $ guidtool 1b2d78d0-47cf-11ec-8d62-0ff591f2a37c -t '2021-11-17 18:03:17' -p 10000