Detections

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

228 detections

The analytic detects the suspicious loading of DLLs by spoolsv.exe, potentially indicating PrintNightmare exploitation. It leverages Sysmon EventCode 7 to identify instances where spoolsv.exe loads multiple DLLs from the Windows System32 spool drivers x64 directory. This activity is significant as it may signify an attacker exploiting the PrintNightmare vulnerability to execute arbitrary code. If confirmed malicious, this could lead to unauthorized code execution, privilege escalation, and persistent access within the environment, posing a severe security risk.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1040
This analytic detects suspicious Kerberos Ticket Granting Ticket (TGT) requests that may indicate exploitation of CVE-2021-42278 and CVE-2021-42287. It identifies sequences where a computer account is renamed (Event ID 4781) and immediately followed by a TGT request (Event ID 4768) for that same account. This behavior is significant as it could represent an attempt to escalate privileges by impersonating a Domain Controller, potentially leading to elevated access and control over the domain environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1039
The following analytic identifies a suspicious modification of the Windows registry setting for max connections per server. It detects changes to specific registry paths using data from the Endpoint.Registry datamodel. This activity is significant because altering this setting can be exploited by attackers to increase the number of concurrent connections to a remote server, potentially facilitating DDoS attacks or enabling more effective lateral movement within a compromised network. If confirmed malicious, this could lead to network disruption or further compromise of additional systems.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0039
This analytic detects the execution of the 'shred' command on a Linux machine, which is used to overwrite files to make them unrecoverable. It leverages data from Linux Auditd, focusing on process names and command-line arguments. This activity is significant because the 'shred' command can be used in destructive attacks, such as those seen in the Industroyer2 malware targeting energy facilities. If confirmed malicious, this activity could lead to the permanent destruction of critical files, severely impacting system integrity and data availability.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0036
The following analytic detects modifications in the Windows registry to disable Windows Error Reporting (WER) settings. It leverages data from the Endpoint.Registry datamodel, specifically monitoring changes to registry paths related to WER with a value set to "0x00000001". This activity is significant as adversaries may disable WER to suppress error notifications, hiding the presence of malicious activities. If confirmed malicious, this could allow attackers to operate undetected, potentially leading to prolonged persistence and further exploitation within the environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0035
The following analytic detects a modification to the Windows registry setting "LongPathsEnabled," which allows file paths longer than 260 characters. This detection leverages data from the Endpoint.Registry datamodel, focusing on changes to the specific registry path and value. This activity is significant because adversaries, including malware like BlackByte, exploit this setting to bypass file path limitations, potentially aiding in evasion techniques. If confirmed malicious, this modification could facilitate the execution of long-path payloads, aiding in persistence and further system compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0035
The following analytic identifies a source endpoint failing to authenticate multiple valid users using the Kerberos protocol, potentially indicating a Password Spraying attack. It leverages Event 4771, which is generated when the Key Distribution Center fails to issue a Kerberos Ticket Granting Ticket (TGT) due to a wrong password (failure code 0x18). This detection uses statistical analysis, specifically the 3-sigma rule, to identify unusual authentication failures. If confirmed malicious, this activity could allow an attacker to gain initial access or elevate privileges within an Active Directory environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
The following analytic detects suspicious modifications to the Windows registry keys related to file compression color and information tips. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the "ShowCompColor" and "ShowInfoTip" values under the "Microsoft\\Windows\\CurrentVersion\\Explorer\\Advanced" path. This activity is significant as it was observed in the Hermetic Wiper malware, indicating potential malicious intent to alter file attributes and user interface elements. If confirmed malicious, this could signify an attempt to manipulate file visibility and deceive users, potentially aiding in further malicious activities.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0033
This analytic detects executables running from public or temporary locations that are communicating over Windows domain authentication ports/protocols such as LDAP (389), LDAPS (636), and Kerberos (88). It leverages network traffic data to identify processes originating from user-controlled directories. This activity is significant because legitimate applications rarely run from these locations and attempt domain authentication, making it a potential indicator of compromise. If confirmed malicious, attackers could leverage this to access domain resources, potentially leading to further exploitation and lateral movement within the network.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0031
The analytic identifies an unusual number of Kerberos service ticket requests (Event ID 4769) originating from a single client address and account. It uses statistical analysis, specifically standard deviation and the 3-sigma rule, to detect anomalies. This activity is significant as it may indicate malicious behavior such as lateral movement, malware staging, or reconnaissance, potentially leading to unauthorized access to multiple endpoints and further compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0029
This analytic identifies a source endpoint failing to authenticate with multiple disabled domain users using the Kerberos protocol. It leverages Windows EventCode 4768, which is generated when the Key Distribution Center issues a Kerberos Ticket Granting Ticket (TGT) and detects failure code `0x12` (credentials revoked). This behavior is significant as it may indicate a Password Spraying attack targeting disabled accounts, potentially leading to initial access or privilege escalation. If confirmed malicious, attackers could gain unauthorized access or elevate privileges within the Active Directory environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0029
Detects Kerberos Ticket-Granting Service (TGS) requests that utilize RC4 encryption. This is often indicative of Kerberoasting attacks, where adversaries request service tickets for Service Principal Names (SPNs) and then attempt to crack the RC4-encrypted hash offline to obtain plaintext credentials. The rule specifically excludes requests from computer accounts (service accounts ending with '$') to reduce false positives.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
0063
This rule detects potential exploitation attempts of CVE-2021-42278, also known as "noPac" or "sAMAccountName spoofing". The exploit involves an attacker creating a computer object with known credentials, then clearing its ServicePrincipalName (SPN) attribute. This manipulation grants the attacker additional permissions on the object, allowing them to make further changes. The detection logic specifically looks for Kerberos Key Distribution Center (KDC) events (EventIDs 35, 36, 37, 38) which indicate anomalies in PAC (Privilege Attribute Certificate) or ticket requests, consistent with the post-exploitation phase of CVE-2021-42278 where forged tickets are used.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
3042
Detects service ticket requests using the weak RC4 encryption type (0x17) for Kerberos, which is often abused in Kerberoasting attacks. The rule specifically looks for Event ID 4769 (A Kerberos service ticket was granted) where the TicketOptions indicate a forwardable and renewable ticket, and the TicketEncryptionType is RC4. It attempts to reduce false positives by excluding service names ending with a dollar sign, which are typically machine accounts.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
4032
Detects failed Kerberos TGT issue operations. This can be a sign of manipulations of TGT messages by an attacker, potentially indicating attempts to exploit Kerberos for credential access or to bypass authentication mechanisms.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
0029
Detects when an Office application loads the 'kerberos.dll' library. This behavior is unusual for standard Office operations and could indicate an attempt to manipulate Kerberos authentication, potentially for credential access or privilege escalation.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1023
This rule detects a potential Kerberos Replay Attack on domain controllers. It specifically looks for Event ID 4649, which indicates that a "KRB_AP_ERR_REPEAT" Kerberos response was sent to the client. This error signifies that the KDC detected a replay of a Kerberos Application Server (AP) request, suggesting an adversary might be attempting to reuse stolen Kerberos tickets to gain unauthorized access.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1022
Detects kerberos TGS request using RC4 encryption which may be indicative of kerberoasting
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
001
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