Masquerading Kerberos Ticket Without a Trailing $ - CVE-2021-42278/42287 (via security)
- Product
- windows
- Service
- security
- Author
- HuntRule
- Published
- 2026-11-08
- Updated
- 2026-11-08
ATT&CK techniques
Priv Esc → Cred AccessRecon
Resource Dev
Initial Access
Execution
Persistence
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects spoof the SAM account name of a a domain controller in order to impersonate it. Vulnerability comes from that computer accounts should have a trailing $ in their name (i.e. sAMAccountName attribute) but no validation process existed until the patch was released. During the offensive phase, attacker will create and rename the sAMAccountName of a computer account to look like the one of a domain controller.
Reporting behind it
- attack.mitre.orghttps://attack.mitre.org/techniques/T1558/
- attack.mitre.orghttps://attack.mitre.org/techniques/T1068/
- exploit.phhttps://exploit.ph/cve-2021-42287-cve-2021-42278-weaponisation.html
- thehacker.recipeshttps://www.thehacker.recipes/ad/movement/kerberos/samaccountname-spoofing
- support.microsoft.comhttps://support.microsoft.com/en-us/topic/kb5008380-authentication-updates-cve-2021-42287-9dafac11-e0d0-4cb8-959a-143bd0201041
- github.comhttps://github.com/WazeHell/sam-the-admin
- github.comhttps://github.com/cube0x0/noPac
- github.comhttps://github.com/ly4k/Pachine
- cloudbrothers.infohttps://cloudbrothers.info/en/exploit-kerberos-samaccountname-spoofing/
- ultimatewindowssecurity.comhttps://www.ultimatewindowssecurity.com/securitylog/encyclopedia/event.aspx?eventID=4768
- ultimatewindowssecurity.comhttps://www.ultimatewindowssecurity.com/securitylog/encyclopedia/event.aspx?eventID=4769
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
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