PoC exploit released for critical AD CS domain-takeover flaw (CVE-2026-54121)

Security researchers released a proof-of-concept exploit for CVE-2026-54121, a critical Active Directory Certificate Services flaw that allows authenticated attackers to obtain forged certificates for domain controller impersonation and full domain compromise. Microsoft patched the vulnerability on 14 July 2026; admins can disable the vulnerable feature via registry until updates are deployed.

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