Suspicious Proxyware Installation via accept-tos Flag on Linux

ATT&CK techniques

Resource Dev → C2

Recon
Resource Dev
- T1608Stage Capabilities
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1090Proxy
Exfiltration
Impact

What it detects

This rule detects a Linux binary being executed with the -accept-tos flag used by residential proxyware agents to silently accept terms and enroll the host. Attackers monetise compromised hosts by installing proxyware, and this non-interactive acceptance flag is characteristic of that abuse.

Reporting behind it

Related detections9 linkedT1090 — drag to rearrange

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Suspicious SOCKS Proxy Autorun Registry Persistence via Registry Set

Suspicious Browser Launched With Injected Proxy Server Argument

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Suspicious Proxyware Installation via accept-tos Flag on Linux

Pivot detection · T1090 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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