It's SHA-512; however, SHA-512 is longer than SHA1!

EDIT: Use the version from my post later on in this thread

-- 2005 through 2012+ variants

SELECT sl.name

, sp.type

, sl.sysadmin

, CAST(sl.password AS VARBINARY(384)) AS EntireSaltAndPasswordHash_HashcatFormat

, LOGINPROPERTY(sl.name,'PasswordHash') AS EntireSaltAndPasswordHashAnotherWay

, CAST(RIGHT(LEFT(sl.password,3),2) AS BINARY(4)) AS Salt

, HASHBYTES('SHA1', CONVERT(VARBINARY,N'Password123') + CAST(LEFT(RIGHT(sl.password,12),2) AS VARBINARY(32))) AS HashBytesReconstructionOfPasswordHashFromAGivenPassword2005

, HASHBYTES('SHA2_512', CONVERT(VARBINARY,N'Password123') + CAST(LEFT(RIGHT(sl.password,34),2) AS VARBINARY(32))) AS HashBytesReconstructionOfPasswordHashFromAGivenPassword2012

FROM sys.syslogins sl

LEFT OUTER JOIN sys.server_principals sp

ON sp.sid = sl.sid

WHERE sl.password IS NOT NULL