Detections

Explore public detection logic contributed by the community across SIEM and rule languages.

3 detections

The following analytic detects the addition of a servicePrincipalName (SPN) containing invisible Unicode characters to an Active Directory computer object via Windows Security Event 5136.
This is the key indicator of the KerberLoss attack (CVE-2026-25177), where an attacker with write access to a machine account's SPN attribute injects a collision SPN that contains a Zero Width or other invisible Unicode character (e.g. U+200C Zero Width Non-Joiner).
LDAP's string preparation rules (RFC 4518) cause these characters to be ignored during uniqueness checking, allowing the write to succeed even when an identical SPN already exists on another machine account.
The Kerberos KDC, however, does not apply the same normalisation — it finds two accounts with matching SPNs and returns KDC_ERR_S_PRINCIPAL_UNKNOWN, causing a Kerberos denial-of-service or forcing clients to fall back to NTLM downgrade.
Splunk Security@SplunkSecurity
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Splunk Security Content
22 days ago
005
The following analytic identifies suspicious PowerShell execution using Script Block Logging (EventCode 4104). It leverages specific patterns and keywords within the ScriptBlockText field to detect potentially malicious activities. This detection is significant for SOC analysts as PowerShell is commonly used by attackers for various malicious purposes, including code execution, privilege escalation, and persistence.
If confirmed malicious, this activity could allow attackers to execute arbitrary commands, exfiltrate data, or maintain long-term access to the compromised system, posing a severe threat to the organization's security.
Splunk Security@SplunkSecurity
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Splunk Security Content
2 months ago
7047
Detects modification of LSA PPL protection settings via CommandLine.
It may indicate an attempt to disable protection and enable credential dumping tools to access LSASS process memory.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
6 months ago
000