# T1132 - Data Encoding

## SOC Recommendation
Investigate Data Encoding activity in the context of Command and Control: confirm scope, affected host/identity, and whether it matches expected administrative behaviour before deciding this is benign.

## D3FEND Mappings
| D3FEND Technique | Relationship | Practical SOC Action |
|---|---|---|
| User Geolocation Logon Pattern Analysis | Detect | Monitor for User Geolocation Logon Pattern Analysis indicators relevant to this technique. |
| Network Traffic Filtering | Isolate | Apply Network Traffic Filtering to contain the blast radius once this technique is observed. |

## Investigation Steps
1. Review Defender for Endpoint / Defender XDR alerts and timeline for the affected host or identity.
2. Check Sentinel analytics rules and incidents correlated with this technique.
3. Review Entra ID sign-in and audit logs if the technique involves an identity or cloud resource.

## Evidence to Collect
- Host or resource affected
- Account or identity involved
- Timestamp of the activity
- Related process, file, or network artifact
- Any preceding or follow-on alerts

## Response Actions
| Action | Risk | Automation Safe | Approval Required |
|---|---|---|---|
| Contain the affected host or account | Medium | No | Yes |
| Collect and preserve evidence | Low | Yes | No |

## KQL
```kql
let threatCategory="Powershell";
let knownUserAgentsIndicators = materialize(externaldata(UserAgent:string, Category:string)
    [ @"https://raw.githubusercontent.com/Azure/Azure-Sentinel/master/Sample%20Data/Feeds/UnusualUserAgents.csv"]
        with(format="csv", ignoreFirstRecord=True));
let knownUserAgents=toscalar(knownUserAgentsIndicators | where Category==threatCategory | where isnotempty(UserAgent) | summarize make_list(UserAgent));
let customUserAgents=toscalar(_GetWatchlist("UnusualUserAgents") | where SearchKey==threatCategory | extend UserAgent=column_ifexists("UserAgent","") | where isnotempty(UserAgent) | summarize make_list(UserAgent));
let fullUAList = array_concat(knownUserAgents,customUserAgents);
_Im_WebSession(httpuseragent_has_any=fullUAList)
| project SrcIpAddr, Url, TimeGenerated, HttpUserAgent, SrcUsername
| extend AccountName = tostring(split(SrcUsername, "@")[0]), AccountUPNSuffix = tostring(split(SrcUsername, "@")[1])
```
```kql
Cisco_Umbrella
| where EventType == "proxylogs"
| where HttpUserAgentOriginal contains "WindowsPowerShell"
| extend Message = "Windows PowerShell User Agent"
| project TimeGenerated, Message, SrcIpAddr, DstIpAddr, UrlOriginal, HttpUserAgentOriginal
```
```kql
let threshold = 15;
let NoteableEvents = SymantecEndpointProtection
| where LogType == "Agent Traffic Logs"
| where Action =~ "Blocked"
| summarize TotalBlockedEvents = count() by UserName
| where TotalBlockedEvents > threshold;
SymantecEndpointProtection
| where LogType =~ "Agent Traffic Logs"
| where Action =~ "Blocked"
| join kind=inner (NoteableEvents) on UserName
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), Total = count() by UserName, RuleName, ServerName, LocalHostIpAddr, LocalPortNumber, TrafficDirection, RemoteHostIpAddr, RemotePortNumber, ApplicationName
```

## Escalation Criteria
- Data Encoding activity observed on a privileged account or critical system.
- Activity follows or precedes other suspicious behaviour in the same investigation.
- Automated triage cannot confidently rule out malicious intent.

## False Positive Considerations
- Legitimate administrative or maintenance activity matching this pattern.
- Approved security testing or red team exercise.
- Known benign software producing similar telemetry.

Generated by SOC Response Atlas by Basyrix.