DnsSystem can upload files from infected machines after receiving a command with uploaddd in the string.2
tool
DnsSystem S1021
- Type
- malware
- Platform
- Windows
- Created
- 24 June 2022
- Last modified
- 16 April 2025
DnsSystem is a .NET based DNS backdoor, which is a customized version of the open source tool DIG.net, that has been used by HEXANE since at least June 2022.[1]
9
Techniques44th pct
7
Tactics68th pct
1
Threat groupunranked
0
CampaignsNone recorded
Enterprise ATT&CK only. Any Mobile or ICS rows on the same ATT&CK page are not carried.
MITRE reference S1021
DnsSystem can use the Windows user name to create a unique identification for infected users and systems.3
DnsSystem can direct queries to custom DNS servers and return C2 commands using TXT records.6
DnsSystem can download files to compromised systems after receiving a command with the string downloaddd.7
Standing S1021
Reach is how much of ATT&CK this tool touches. Coverage is how well defended each thing it does is, as a median per technique rather than a total — a total would just restate the reach. Each figure is ranked against all 825 ATT&CK software entries only where that population actually spreads. Where most of the population shares one value, a percentile would rank the tie instead of the entity, so the raw value is shown and no rank is claimed.
Reach
Techniques944th pct
44th percentile · 56% of 825 ATT&CK software entries have more Enterprise techniques.
Tactics768th pct
68th percentile · 68% of 825 ATT&CK software entries have this many tactics spanned or fewer.
Threat group161% tie · 22 values
61% of the population shares a single value across only 22 distinct values, so a percentile here would rank the tie, not the entity.
Campaigns085% tie · 8 values
85% of the population shares a single value across only 8 distinct values, so a percentile here would rank the tie, not the entity.
Coverage
Rules / technique46medTop 10%
90th percentile · 90% of 825 ATT&CK software entries have this many detection rules per technique or fewer.
Tests / technique6med
Detection coverage S1021
408 distinct rules cover the 9 techniques recorded for this tool. The 423 technique-to-rule mappings resolve to 408 distinct rules, because one rule can cover several techniques. 280 Sigma · 128 Splunk.
9 covered by at least one rule408 distinct rules in total
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