The function _ipconfig_getnode() in the uuid module can incorrectly pick up an IPv6 DUID instead of a MAC address due to not validating an exact match for the regular expression. The following output from `ipconfig /all` on my machine can be used to illustrate the problem:
```
C:\Users\viz_s>ipconfig /all
Windows IP Configuration
Host Name . . . . . . . . . . . . : DESKTOP-UOHALF9
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
Ethernet adapter vEthernet (Default Switch):
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Hyper-V Virtual Ethernet Adapter
Physical Address. . . . . . . . . : 02-15-0B-EF-A2-34
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::d8b5:2fbd:4d82:2e95%12(Preferred)
IPv4 Address. . . . . . . . . . . : 192.168.125.17(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.240
Default Gateway . . . . . . . . . :
DHCPv6 IAID . . . . . . . . . . . : 452990301
DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-1F-5A-B1-27-98-5F-D3-C5-71-45
DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1
fec0:0:0:ffff::2%1
fec0:0:0:ffff::3%1
NetBIOS over Tcpip. . . . . . . . : Disabled
Ethernet adapter vEthernet (DockerNAT):
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Hyper-V Virtual Ethernet Adapter #2
Physical Address. . . . . . . . . : 00-15-5D-00-0D-1C
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::a8b0:4970:fe5c:7ad8%20(Preferred)
IPv4 Address. . . . . . . . . . . : 10.0.75.1(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . :
DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1
fec0:0:0:ffff::2%1
fec0:0:0:ffff::3%1
NetBIOS over Tcpip. . . . . . . . : Enabled
Ethernet adapter Npcap Loopback Adapter:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Npcap Loopback Adapter
Physical Address. . . . . . . . . : 02-00-4C-4F-4F-50
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::c07f:d604:86b:87e0%26(Preferred)
Autoconfiguration IPv4 Address. . : 169.254.135.224(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.0.0
Default Gateway . . . . . . . . . :
DHCPv6 IAID . . . . . . . . . . . : 771883084
DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-1F-5A-B1-27-98-5F-D3-C5-71-45
DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1
fec0:0:0:ffff::2%1
fec0:0:0:ffff::3%1
NetBIOS over Tcpip. . . . . . . . : Enabled
Wireless LAN adapter Local Area Connection* 2:
Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft Wi-Fi Direct Virtual Adapter
Physical Address. . . . . . . . . : 9A-5F-D3-C5-70-44
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Wireless LAN adapter Local Area Connection* 12:
Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft Wi-Fi Direct Virtual Adapter #2
Physical Address. . . . . . . . . : 9A-5F-D3-C5-75-44
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Wireless LAN adapter Wi-Fi:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Marvell AVASTAR Wireless-AC Network Controller
Physical Address. . . . . . . . . : 98-5F-D3-C5-71-45
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::f183:815e:4914:dfa%21(Preferred)
IPv4 Address. . . . . . . . . . . : 100.69.161.39(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.0.0
Lease Obtained. . . . . . . . . . : Wednesday, May 16, 2018 8:51:32 AM
Lease Expires . . . . . . . . . . : Wednesday, May 16, 2018 9:51:31 AM
Default Gateway . . . . . . . . . : 100.69.0.5
DHCP Server . . . . . . . . . . . : 100.69.0.6
DHCPv6 IAID . . . . . . . . . . . : 144203731
DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-1F-5A-B1-27-98-5F-D3-C5-71-45
DNS Servers . . . . . . . . . . . : 100.69.0.5
NetBIOS over Tcpip. . . . . . . . : Enabled
```
|