S1021: DnsSystem
Security context for executives and security teams
S1021: DnsSystem describes [DnsSystem](https://attack.mitre.org/software/S1021) is a .NET based DNS backdoor, which is a customized version of the open source tool DIG.net, that has been used by [HEXANE](https://attack.mitre.org/groups/G1001) since at least June 2022.(Citation: Zscaler Lyceum DnsSystem June 2022)
Executive priority
S1021: DnsSystem is an official MITRE ATT&CK software. Glexia treats it as defensive behavior context for prioritizing monitoring, control validation, and response planning without using the object by itself as an attribution claim.
Technical view
Security teams should validate S1021: DnsSystem by reviewing the official ATT&CK relationships, mapped tactics (the mapped ATT&CK tactic context), supported platforms (Windows), and available local telemetry before making detection or mitigation decisions.
Likely telemetry
- Official ATT&CK relationships and object metadata
- Network, endpoint, and security-tool telemetry
Detection direction
- Validate whether S1021: DnsSystem appears in your detection coverage and tabletop scenarios.
- Use the object to align executive risk language with SOC, incident response, and detection engineering work.
- Do not treat ATT&CK relationship context as attribution without corroborating evidence.
Mitigation priorities
- Map the object to existing controls and identify missing telemetry or response ownership.
- Prioritize mitigations that reduce exposure on the listed platforms and tactics.
- Review adjacent ATT&CK relationships before changing policy, detections, or reporting language.
Additional notes and limits
Baseline Glexia take generated from the official MITRE ATT&CK STIX object, source hash, tactics, platforms, and detection fields. It is safe to replace with a richer model-generated take for the same source hash later.
This baseline take is source-grounded and schema-validated, but it does not include environment-specific telemetry, incident evidence, or threat-intelligence corroboration.
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
DnsSystem
How security teams should use this page
Treat this object as behavior context, not an attribution claim. Validate the related groups, software, data sources, and mitigations against official ATT&CK relationships and your own telemetry before making control-coverage decisions.
Techniques used
This mirrors the MITRE pattern of making group, software, campaign, and technique relationships scannable. Relationship notes come from mirrored ATT&CK relationship text when available.
| Domain | ID | Name | Relationship / procedure |
|---|---|---|---|
| Enterprise | T1132.001 | Standard EncodingSub-technique | |
| Enterprise | T1041 | Exfiltration Over C2 Channel | |
| Enterprise | T1105 | Ingress Tool Transfer | |
| Enterprise | T1071.004 | DNSSub-technique | |
| Enterprise | T1059.003 | Windows Command ShellSub-technique | |
| Enterprise | T1547.001 | Registry Run Keys / Startup FolderSub-technique | |
| Enterprise | T1033 | System Owner/User Discovery | |
| Enterprise | T1005 | Data from Local System | |
| Enterprise | T1204.002 | Malicious FileSub-technique |
Groups, software, and campaigns
G1001: HEXANE
HEXANE is a cyber espionage threat group that has targeted oil & gas, telecommunications, aviation, and internet service provider organizations since at least 2017. Targeted companies have been located in the Middle East and Africa, including Israel, Saudi Arabia, Kuwait, Morocco, and Tunisia. HEXANE's TTPs appear similar to APT33 and OilRig but due to differences in victims and tools it is tracked as a separate entity.[1][2][3][4]
All related ATT&CK context
Object version and sync metadata
The fields below describe the current mirrored snapshot. When Glexia retains multiple ATT&CK source imports, you can open the table to compare the same object across releases (hashes and MITRE timestamps). For MITRE’s own release notes and roadmap, see ATT&CK resources — Updates.
Imported snapshots across ATT&CK releases(2)
| Release | Bundle imported | Object version | Modified | Status | Raw hash |
|---|---|---|---|---|---|
| 19.2 | 1.0 | Current bundle | e357e4eeb9e9… | ||
| 19.1 | 1.0 | Older bundle | e357e4eeb9e9… |
Mirrored ATT&CK source object
The raw object is retained through the mirrored ATT&CK source bundle and object hash. The raw endpoint returns the exact object from the mirrored bundle when available.
External references and citations
MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.
- [1]Zscaler Lyceum DnsSystem June 2022
Shivtarkar, N. and Kumar, A. (2022, June 9). Lyceum .NET DNS Backdoor. Retrieved June 23, 2022.
Open source URL - [2]mitre-attackS1021Open source URL
Source: MITRE ATT&CK®. © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. MITRE ATT&CK and ATT&CK are registered trademarks of The MITRE Corporation. Glexia is not affiliated with or endorsed by MITRE.