The code that resolves A/AAAA records for domain controllers in Get-WinADForestControllerInformation is mistakenly including A/AAAA records returned in the "Additional" section of the DNS response. This can lead to an invalid result for the IPAddress* properties in the output object.
As an example that can be publicly queried, take a look at the response for github.com. There is only a single A record in the Answer section. But there are a whole bunch of NS records in the Authority section and corresponding A records for those NS records in the Additional section. So when the code in the function filters only on the Type property, it mistakenly grabs those A records from the additional section as well.
PS> Resolve-DnsName github.com -DnsOnly | Where-Object { $_.Type -eq 'A' }
Name Type TTL Section IPAddress
---- ---- --- ------- ---------
github.com A 2 Answer 140.82.114.4
dns1.p08.nsone.net A 59995 Additional 198.51.44.8
dns2.p08.nsone.net A 59995 Additional 198.51.45.8
dns3.p08.nsone.net A 59995 Additional 198.51.44.72
dns4.p08.nsone.net A 59995 Additional 198.51.45.72
ns-1283.awsdns-32.org A 88165 Additional 205.251.197.3
ns-1707.awsdns-21.co.uk A 88166 Additional 205.251.198.171
ns-520.awsdns-01.net A 88166 Additional 205.251.194.8
The code should ideally be updated to only include results in the Answer section.
PrzemyslawKlys
commented
3 years ago
The code that resolves A/AAAA records for domain controllers in
Get-WinADForestControllerInformationis mistakenly including A/AAAA records returned in the "Additional" section of the DNS response. This can lead to an invalid result for theIPAddress*properties in the output object.https://github.com/EvotecIT/ADEssentials/blob/8b9b71a40a5435cf03b94505303db86fe894f7eb/Public/Get-WinADForestControllerInformation.ps1#L51-L55
As an example that can be publicly queried, take a look at the response for
github.com. There is only a single A record in the Answer section. But there are a whole bunch of NS records in the Authority section and corresponding A records for those NS records in the Additional section. So when the code in the function filters only on theTypeproperty, it mistakenly grabs those A records from the additional section as well.The code should ideally be updated to only include results in the Answer section.