CLI environment overrides

February 27, 2026 ยท View on GitHub

This page covers flags that shape the emulated host environment and behavior determinism.

Host, user, and OS identity

Primary flags:

  • --hostname
  • --domain
  • --user-name
  • --user-is-admin / --no-user-is-admin
  • --user-sid
  • --os-ver-major, --os-ver-minor, --os-ver-release, --os-ver-build

Example: enterprise-like identity profile

speakeasy -t sample.exe \
  --hostname WS-3471 \
  --domain CORP \
  --user-name jdoe \
  --user-sid S-1-5-21-1111111111-2222222222-3333333333-1107 \
  --no-user-is-admin \
  --os-ver-major 10 \
  --os-ver-minor 0 \
  --os-ver-build 19045 \
  -v -o report.json 2> run.log

Quick verification:

rg "(hostname|domain|user\.name|user\.sid|user\.is_admin|os_ver\.)" run.log

Process context and environment variables

Primary flags:

  • --current-dir
  • --command-line
  • --env KEY=VALUE (repeatable)

Example:

speakeasy -t sample.exe \
  --current-dir 'C:\\ProgramData\\Microsoft' \
  --command-line 'svchost.exe -k netsvcs -p' \
  --env TEMP=C:\\Windows\\Temp \
  --env APPDATA=C:\\Users\\jdoe\\AppData\\Roaming \
  --env COMPUTERNAME=WS-3471 \
  -v -o report.json 2> run.log

Quick verification:

rg "(current_dir|command_line|env =)" run.log

DNS override mappings

Primary flag:

  • --network-dns-names HOST=IP (repeatable)

Example: force known C2 host resolutions

speakeasy -t sample.exe \
  --network-dns-names c2-a.example=203.0.113.10 \
  --network-dns-names c2-b.example=203.0.113.11 \
  -o report.json

Quick verification:

jq '.entry_points[].events[]? | select(.event == "net_dns") | {query, response}' report.json

Module load policy and decoy module directories

Some samples (especially shellcode) parse PE export tables directly to resolve API pointers. When expected modules or exports are missing, these controls let you choose strict or permissive behavior.

Primary flags:

  • --modules-modules-always-exist / --no-modules-modules-always-exist
  • --modules-functions-always-exist / --no-modules-functions-always-exist
  • --modules-module-directory-x86
  • --modules-module-directory-x64

Example: relaxed unresolved-import policy with custom decoys

speakeasy -t sample.exe \
  --modules-modules-always-exist \
  --modules-functions-always-exist \
  --modules-module-directory-x86 /opt/decoys/x86 \
  --modules-module-directory-x64 /opt/decoys/x64 \
  -o report.json

Use this when triaging samples that otherwise stop early on missing modules/APIs.

API hammering controls

Primary flags:

  • --api-hammering-enabled / --no-api-hammering-enabled
  • --api-hammering-threshold
  • --api-hammering-allow-list VALUE (repeatable)

Example:

speakeasy -t sample.exe \
  --api-hammering-enabled \
  --api-hammering-threshold 5000 \
  --api-hammering-allow-list kernel32.WriteFile \
  --api-hammering-allow-list kernel32.ReadFile \
  -o report.json

This is useful when balancing anti-loop containment with legitimate hot API usage.