Browse Rules

Search and filter across all detection sources

12 rules

sigma high sigma

ADCS - Certighost Certificate Issued via CDC Chase (CVE-2026-54121)

Detects successful issuance of an ADCS certificate where the request attributes include 'cdc' (Client DC) or 'rmd' (Remote Domain) pointing to a non-DC domain or IP, confirming the CA's chase fallback path was taken against an attacker-controlled target. 'cdc' directs the CA to an address for identity lookup; 'rmd' specifies the principal to look up there. In an attack (CVE-2026-54121, Certighost), cdc points to a rogue host that returns a forged DC identity. A successfully issued certificate a

hayabusa high sigma

ADCS - Certighost Certificate Issued via CDC Chase (CVE-2026-54121)

Detects successful issuance of an ADCS certificate where the request attributes include 'cdc' (Client DC) or 'rmd' (Remote Domain) pointing to a non-DC domain or IP, confirming the CA's chase fallback path was taken against an attacker-controlled target. 'cdc' directs the CA to an address for identity lookup; 'rmd' specifies the principal to look up there. In an attack (CVE-2026-54121, Certighost), cdc points to a rogue host that returns a forged DC identity. A successfully issued certificate a

hayabusa high sigma

DC Machine Account TGT Request from Non-DC Source IP

Detects a Kerberos TGT request (Event 4768) for a known Domain Controller machine account originating from an IP address that is not a known Domain Controller. DC machine accounts should only request TGTs from their own IP. Any TGT request for a DC account from a workstation or non-DC host is anomalous and indicates one of the following: - PKINIT abuse (CVE-2026-54121 / Certighost): attacker authenticating as a DC via a forged certificate from their workstation - Overpass-the-Hash: atta

sigma high sigma

ADCS - Certighost Ghost Machine Account Creation

Detects the creation of a machine account whose name starts with 'GHOST', which is the naming convention used by the CVE-2026-54121 (Certighost) exploit tooling. The public proof-of-concept for Certighost creates a temporary machine account with a name of the form GHOST<random>$ before enrolling for a DC certificate via the cdc chase path. The attacker-controlled machine account is used as the requester identity in the certificate request; the cdc attribute then redirects the CA to a rogue host

hayabusa high sigma

ADCS - Certighost Ghost Machine Account Creation

Detects the creation of a machine account whose name starts with 'GHOST', which is the naming convention used by the CVE-2026-54121 (Certighost) exploit tooling. The public proof-of-concept for Certighost creates a temporary machine account with a name of the form GHOST<random>$ before enrolling for a DC certificate via the cdc chase path. The attacker-controlled machine account is used as the requester identity in the certificate request; the cdc attribute then redirects the CA to a rogue host

sigma high sigma

ADCS - Certighost CDC Chase Certificate Request (CVE-2026-54121)

Detects Active Directory Certificate Services (ADCS) certificate requests that include the 'cdc' (Client DC) request attribute pointing to a domain or IP that is not a known Domain Controller. 'cdc' is an optional MS-WCCE enrollment attribute designed for cross-domain/cross-forest scenarios where a client in a child domain tells the CA which DC to contact for identity lookups when the CA cannot reach that domain directly. Legitimate values are DC hostnames or IPs that resolve to a real Domain C

hayabusa high sigma

ADCS - Certighost CDC Chase Certificate Request (CVE-2026-54121)

Detects Active Directory Certificate Services (ADCS) certificate requests that include the 'cdc' (Client DC) request attribute pointing to a domain or IP that is not a known Domain Controller. 'cdc' is an optional MS-WCCE enrollment attribute designed for cross-domain/cross-forest scenarios where a client in a child domain tells the CA which DC to contact for identity lookups when the CA cannot reach that domain directly. Legitimate values are DC hostnames or IPs that resolve to a real Domain C

elastic high kql

Potential CertiGhost AD CS Machine Identity Mismatch (CVE-2026-54121)

Identifies successful Active Directory Certificate Services (AD CS) certificate issuance events where a machine-account requester differs from the Remote Machine Discovery (RMD) chase target while the event's DNS subject alternative name (SAN) matches that target. This requester-to-target mismatch may indicate CertiGhost (CVE-2026-54121) or similar abuse of AD CS request-context chase processing.

sigma medium sigma

Suspicious Machine Account Replication - DcSync Indicator

Detects suspicious Active Directory Replication Service (ADRS) requests originating from a machine account (SubjectUserName ending in '$') rather than a legitimate Domain Controller. Under normal operation, only Domain Controllers initiate replication requests carrying the DS-Replication-Get-Changes-All right. If a threat actor obtains valid machine account credentials — for example by abusing certificate-based authentication (PKINIT) to impersonate a DC after exploiting a CA vulnerability such

hayabusa medium sigma

Suspicious Machine Account Replication - DcSync Indicator

Detects suspicious Active Directory Replication Service (ADRS) requests originating from a machine account (SubjectUserName ending in '$') rather than a legitimate Domain Controller. Under normal operation, only Domain Controllers initiate replication requests carrying the DS-Replication-Get-Changes-All right. If a threat actor obtains valid machine account credentials — for example by abusing certificate-based authentication (PKINIT) to impersonate a DC after exploiting a CA vulnerability such

hayabusa high sigma

DC Machine Account TGS Request from Non-DC Source IP

Detects a Kerberos service ticket request (Event 4769) targeting a Domain Controller machine account's service (e.g. DRSUAPI) originating from an IP address that is not a known Domain Controller. Service tickets for DC machine accounts should only be requested by other DCs during legitimate replication operations. An attacker with a valid TGT (obtained via PKINIT, overpass-the-hash, or stolen TGT) targeting a DC machine account's service from a workstation IP indicates preparation for DCSync or

hayabusa critical sigma

DC Machine Account Network Logon from Non-DC Source IP

Detects a Domain Controller machine account authenticating from a source IP that is not a known Domain Controller. DC machine accounts should only authenticate locally or from other DCs during replication operations. Any logon event for a DC account from a workstation or non-DC host is anomalous and indicates one of the following: - Silver Ticket: attacker forged a Kerberos TGS for a DC machine account without requesting a TGT - Pass-the-Ticket: attacker is replaying a captured DC machi