Mustard Tempest has used the filename AutoUpdater.js to mimic legitimate update files and has also used the Cyrillic homoglyph characters С (0xd0a1) and а (0xd0b0), to produce the filename Сhrome.Updаte.zip.56
Mustard Tempest has sent victims emails containing links to compromised websites.15
Initial Access13 detection rules
Standing G1020
Reach is how much of ATT&CK this group 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 176 ATT&CK groups 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
Techniques1239th pct
39th percentile · 61% of 176 ATT&CK groups have more Enterprise techniques.
Tactics634th pct
34th percentile · 66% of 176 ATT&CK groups have more tactics spanned.
Tools & malware239th pct
39th percentile · 61% of 176 ATT&CK groups have more tools and malware.
Campaigns089% tie · 4 values
89% of the population shares a single value across only 4 distinct values, so a percentile here would rank the tie, not the entity.
Coverage
Rules / technique3.5medBottom 9%
9th percentile · 91% of 176 ATT&CK groups have more detection rules per technique.
Tests / technique0medBottom 16%
16th percentile · 84% of 176 ATT&CK groups have more atomic tests per technique.
Data comps / technique3.5med65% tie · 12 values
65% of the population shares a single value across only 12 distinct values, so a percentile here would rank the tie, not the entity.
Mitigations / technique1med43% tie · 11 values
43% of the population shares a single value across only 11 distinct values, so a percentile here would rank the tie, not the entity.
5 of 8 axes carry an honest rank on this page. Coverage medians are taken across this group’s 12 Enterprise techniques.
Range
Technique Campaign use over its cumulative rule count.
The following analytic detects the execution of tools commonly exploited by cybercriminals, such as those used for unauthorized access, network scanning, privilege escalation, password dumping or data exfiltration. (...)
Detects the Linux-specific execution chain of the plain-crypto-js malicious npm dependency by Axios NPM package, including payload download via curl and detached execution using nohup and python3. (...)
Detects the macOS-specific execution chain of the plain-crypto-js malicious npm dependency in Axios NPM Package, including AppleScript execution via osascript, payload download, permission modification, execution, and cleanup.
This analytic detects potential reconnaissance activities on Cisco ASA devices by identifying execution of multiple information-gathering "show" commands within a short timeframe. (...)
This analytic detects unexpected outbound network connections initiated by known webserver processes such as `httpd.exe`, `nginx.exe`, or `tomcat.exe` to common file sharing or public content hosting services like GitHub, Discord CDN, Transfer.sh, or Pastebin. (...)
The following analytic detects potential reverse shell activity by identifying connections involving ports commonly associated with remote access tools, shell listeners, or tunneling utilities. (...)
The following analytic detects connections with a high Encrypted Visibility Engine (EVE) threat confidence score, indicating potentially malicious behavior within encrypted traffic. (...)
This analytic identifies Snort intrusion signatures that have been triggered by ten or more distinct internal IP addresses within a one-hour window. (...)
The following analytic detects the execution of the curl utility where the command line includes percent-encoded characters and explicit file output options (such as -o or --output). (...)
The following analytic identifies specific GET or HEAD requests to web servers that indicate reconnaissance attempts to find vulnerable JBoss servers. (...)