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Rule Reference

SEC708lintai-ai-securitystableclaude_settingswarn

Claude settings: screen capture exfiltration hook

Claude settings command hook captures and exfiltrates a screenshot or desktop image

Provider
lintai-ai-security
Surface
claude_settings
Scope
per_file
Tier
stable
Severity
warn
Confidence
high
Detection
structural
Remediation
message_only

Activation Model

Preset Membership

This rule is part of the builtin activation graph through these preset memberships.

basemembership
claudemembership

Lifecycle

Stable Lifecycle Contract

State

stable_gated

Graduation rationale

Checks committed Claude settings command hooks for explicit screen capture utilities combined with remote transfer behavior.

Deterministic signal basis

ClaudeSettingsSignals command-hook string analysis over committed hook entries with type == command for explicit screen capture utilities such as `screencapture`, `scrot`, `gnome-screenshot`, `grim`, `maim`, `grimshot`, ImageMagick `import -window root`, or PowerShell `CopyFromScreen`, combined with remote sinks such as `curl`, `wget`, `scp`, `rsync`, `nc`, or HTTP(S) endpoints.

Malicious corpus
claude-settings-hook-screen-capture-exfil
Benign corpus
claude-settings-network-command-safe
structured evidence required remediation reviewed
Canonical note

Structural stable rule intended as a high-precision check with deterministic evidence.

Nearby Signals

Related Rules

SEC340Claude hook: mutable package launcherClaude settings command hook uses a mutable package launcherclaude_settingsstable
SEC341Claude hook: remote content piped to shellClaude settings command hook downloads remote content and pipes it into a shellclaude_settingsstable
SEC342Claude hook: TLS verification disabledClaude settings command hook disables TLS verification in a network-capable execution pathclaude_settingsstable
SEC641Claude settings: command hook root deletionClaude settings command hook attempts destructive root deletionclaude_settingsstable
SEC642Claude settings: command hook password file accessClaude settings command hook accesses a sensitive system password fileclaude_settingsstable
SEC643Claude settings: command hook shell profile writeClaude settings command hook writes to a shell profile startup fileclaude_settingsstable

Why It Matters ​

Capturing the desktop and transmitting it from a committed Claude hook is high-confidence surveillance and data theft behavior.

What Triggers ​

SEC708 matches committed Claude settings command hooks that invoke explicit screen capture utilities such as screencapture, scrot, gnome-screenshot, grim, grimshot, maim, ImageMagick import -window root, or PowerShell CopyFromScreen, and also transmit data to remote sinks such as curl, wget, scp, rsync, nc, or HTTP(S) endpoints.

False Positives ​

Shared committed Claude hooks should not capture and transmit screenshots. Legitimate screen sharing should be deliberate user action, not hidden committed automation.

Remediation ​

Remove screenshot capture and remote transfer behavior from the committed Claude hook and keep screen data local unless the user explicitly chooses to share it.