> For the complete documentation index, see [llms.txt](https://cortex-docs.paloaltonetworks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cortex-docs.paloaltonetworks.com/analytics-alerts/alerts-by-name/possible-dcsync-attack.md).
# Possible DCSync attack
### Synopsis
| Field | Value |
| -------------------- | -------------------------------------------- |
| Activation Period | 14 Days |
| Training Period | 30 Days |
| Test Period | N/A (single event) |
| Deduplication Period | 1 Day |
| Required Data | XDR Agent with eXtended Threat Hunting (XTH) |
| Detection Modules | Identity Analytics |
| ATT\&CK Tactic | Credential Access (TA0006) |
| ATT\&CK Technique | OS Credential Dumping: DCSync (T1003.006) |
| Severity | Informational |
### Description
A GetNCChanges replication request was observed that requests all changes for an object (USN starting from 0 with no up-to-date vector), which may indicate an attempt to dump credentials.
### Attacker's Goals
* An attacker can abuse replication to dump credentials from the Domain Controller.
### Investigative actions
* Check for a suspicious process on the initiator.
* Check for users that logged-in to the actor ip and investigate their actions.
* Check for indicators of compromise on the actor ip.
### Variations
Possible DCSync attack using Impacket-like tool
**Synopsis**
| Field | Value |
| ----------------- | ----------------------------------------- |
| ATT\&CK Tactic | Credential Access (TA0006) |
| ATT\&CK Technique | OS Credential Dumping: DCSync (T1003.006) |
| Severity | Medium |
**Description**
A GetNCChanges replication request was observed that requests all changes for a single object, with parameters matching a known Impacket secretsdump DCSync signature.
**Attacker's Goals**
* An attacker can abuse replication to dump credentials from the Domain Controller.
**Investigative actions**
* Check for a suspicious process on the initiator.
* Check for users that logged-in to the actor ip and investigate their actions.
* Check for indicators of compromise on the actor ip.
Possible DCSync attack using Mimikatz-like tool
**Synopsis**
| Field | Value |
| ----------------- | ----------------------------------------- |
| ATT\&CK Tactic | Credential Access (TA0006) |
| ATT\&CK Technique | OS Credential Dumping: DCSync (T1003.006) |
| Severity | Low |
**Description**
A GetNCChanges replication request was observed that requests all changes for a single object, with parameters matching a known Mimikatz lsadump::dcsync signature.
**Attacker's Goals**
* An attacker can abuse replication to dump credentials from the Domain Controller.
**Investigative actions**
* Check for a suspicious process on the initiator.
* Check for users that logged-in to the actor ip and investigate their actions.
* Check for indicators of compromise on the actor ip.
Possible DCSync attack using unknown tool
**Synopsis**
| Field | Value |
| ----------------- | ----------------------------------------- |
| ATT\&CK Tactic | Credential Access (TA0006) |
| ATT\&CK Technique | OS Credential Dumping: DCSync (T1003.006) |
| Severity | Low |
**Description**
A GetNCChanges replication request was observed with parameters that resemble known credential dumping tools, though the specific tool could not be identified.
**Attacker's Goals**
* An attacker can abuse replication to dump credentials from the Domain Controller.
**Investigative actions**
* Check for a suspicious process on the initiator.
* Check for users that logged-in to the actor ip and investigate their actions.
* Check for indicators of compromise on the actor ip.
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