Esc8

Overview Machine author: xct. Windows Server Domain Controller. Domain: cicada.vl. Host: DC-JPQ225. Kill chain: a password on a sticky note in an image from an open NFS share, Kerberos authentication (NTLM disabled), ADCS vulnerable to ESC8, a Kerberos relay (bypassing the self-relay block) plus PetitPotam coercion, a certificate as the DC machine account, DCSync, the Administrator hash, a shell. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 [NFS 2049] share /profiles (everyone) | exfil vacation.png + marketing.png v [OSINT/image] password on a sticky note: Rosie.Powell : Cicada123 | auth ONLY via Kerberos (NTLM disabled) v [ADCS] certipy find -> CA vulnerable to ESC8 (Web Enrollment over HTTP) | NTLM self-relay blocked + NTLM disabled -> need a Kerberos relay v [DNS + coercion] bloodyAD: a DNS record with a serialized empty CREDENTIAL_TARGET_INFORMATION | PetitPotam forces the DC to auth to us v [certipy relay] Kerberos relay -> /certsrv/certfnsh.asp -> cert for DC-JPQ225$ v [certipy auth] PKINIT -> TGT + machine-account NT hash v [secretsdump] DCSync -> Administrator hash v [wmiexec] shell as cicada\administrator -> user.txt + root.txt The key lesson: how to perform ESC8 in an environment where NTLM is fully disabled, so the classic NTLM relay does not work. The solution is a Kerberos relay using a crafted DNS record containing a serialized (empty) CREDENTIAL_TARGET_INFORMATION structure, which bypasses the self-relay restriction. ...