ClawHub

Cron Scheduler

Security checks across malware telemetry and agentic risk

Overview

This cron-management skill is functional and mostly disclosed, but it can create persistent scheduled commands, delete cron entries, and run sudo service-control actions without enough guardrails.

Install only if you intentionally want an agent-assisted tool that can change your crontab. Review every schedule, command, removal line number, and pattern before running it; make a backup first; and approve sudo service actions only when you knowingly want to affect the whole machine's cron daemon.

SkillSpector

By NVIDIA
Vulnerability Patterns
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
  • Excessive AgencyUnrestricted Tool Access, Autonomous Decision Making, Scope Creep
  • Rogue AgentSelf-Modification, Session Persistence
  • Trigger AbuseOverly Broad Trigger, Shadow Command Trigger, Keyword Baiting Trigger
  • MCP Tool PoisoningHidden Instructions, Unicode Deception, Parameter Description Injection
Findings (19)

Description-Behavior Mismatch

Medium
Confidence
95% confidence
Finding
The skill exceeds its stated purpose of managing user cron entries by also starting, stopping, and querying the cron system service with sudo. That broadens the trust boundary from per-user task management to privileged system administration, which is dangerous in an agent context because a natural-language request about cron jobs could trigger system-wide service changes.

Context-Inappropriate Capability

Medium
Confidence
96% confidence
Finding
These privileged launchctl/systemctl operations are not necessary for the minimum capability of editing a user's crontab. In an automation setting, unnecessary privileged actions increase blast radius and make prompt-induced misuse more severe, even if the commands themselves are legitimate admin operations.

Vague Triggers

Medium
Confidence
87% confidence
Finding
The trigger phrase "cron" is extremely broad and likely to match ordinary discussion about cron rather than an explicit request to invoke this skill. In an agent environment, overly broad activation can cause unintended execution of actions that modify scheduled tasks or system state, especially given this skill can add/remove jobs and control the cron service.

Vague Triggers

Medium
Confidence
84% confidence
Finding
The phrases "schedule task" and "recurring task" are ambiguous and common in everyday language, so they may activate the skill when a user is speaking generally rather than asking to manipulate cron. Because the skill performs persistent system changes, accidental invocation could lead to unintended cron entries, removals, or service operations.

Missing User Warnings

Medium
Confidence
89% confidence
Finding
remove_job rewrites the user's entire crontab immediately, without a preview or confirmation prompt. In an agent workflow, a mistaken line number, broad pattern, or adversarial prompt could silently delete scheduled jobs and disrupt persistence, backups, or operational tasks.

Missing User Warnings

Medium
Confidence
94% confidence
Finding
The service-management path invokes privileged system commands without a prior warning that it may prompt for sudo and affect the entire host. In an agent setting, lack of disclosure materially increases the risk of unintended system changes or social-engineering-assisted approval of privileged operations.

Sudo/Root Execution

Medium
Category
Privilege Escalation
Content
macos)
            case "$action" in
                start)
                    sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.cron.plist 2>/dev/null || \
                    log_error "Need sudo to start cron"
                    ;;
                stop)
Confidence
93% confidence
Finding
sudo

Sudo/Root Execution

Medium
Category
Privilege Escalation
Content
log_error "Need sudo to start cron"
                    ;;
                stop)
                    sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.cron.plist 2>/dev/null || \
                    log_error "Need sudo to stop cron"
                    ;;
                status)
Confidence
93% confidence
Finding
sudo

Sudo/Root Execution

Medium
Category
Privilege Escalation
Content
log_error "Need sudo to stop cron"
                    ;;
                status)
                    if sudo launchctl list | grep -q com.apple.cron; then
                        log_success "Cron service is running"
                    else
                        log_warn "Cron service is not running"
Confidence
88% confidence
Finding
sudo

Sudo/Root Execution

Medium
Category
Privilege Escalation
Content
linux)
            case "$action" in
                start)
                    sudo systemctl start cron 2>/dev/null || sudo systemctl start crond 2>/dev/null || \
                    log_error "Failed to start cron service"
                    ;;
                stop)
Confidence
94% confidence
Finding
sudo

Sudo/Root Execution

Medium
Category
Privilege Escalation
Content
linux)
            case "$action" in
                start)
                    sudo systemctl start cron 2>/dev/null || sudo systemctl start crond 2>/dev/null || \
                    log_error "Failed to start cron service"
                    ;;
                stop)
Confidence
94% confidence
Finding
sudo

Sudo/Root Execution

Medium
Category
Privilege Escalation
Content
log_error "Failed to start cron service"
                    ;;
                stop)
                    sudo systemctl stop cron 2>/dev/null || sudo systemctl stop crond 2>/dev/null || \
                    log_error "Failed to stop cron service"
                    ;;
                status)
Confidence
94% confidence
Finding
sudo

Sudo/Root Execution

Medium
Category
Privilege Escalation
Content
log_error "Failed to start cron service"
                    ;;
                stop)
                    sudo systemctl stop cron 2>/dev/null || sudo systemctl stop crond 2>/dev/null || \
                    log_error "Failed to stop cron service"
                    ;;
                status)
Confidence
94% confidence
Finding
sudo

Sudo/Root Execution

Medium
Category
Privilege Escalation
Content
log_error "Failed to stop cron service"
                    ;;
                status)
                    if sudo systemctl is-active cron &>/dev/null || sudo systemctl is-active crond &>/dev/null; then
                        log_success "Cron service is running"
                    else
                        log_warn "Cron service is not running"
Confidence
86% confidence
Finding
sudo

Sudo/Root Execution

Medium
Category
Privilege Escalation
Content
log_error "Failed to stop cron service"
                    ;;
                status)
                    if sudo systemctl is-active cron &>/dev/null || sudo systemctl is-active crond &>/dev/null; then
                        log_success "Cron service is running"
                    else
                        log_warn "Cron service is not running"
Confidence
86% confidence
Finding
sudo

Session Persistence

Medium
Category
Rogue Agent
Content
local temp_file
    temp_file=$(mktemp)
    
    # Preserve existing crontab
    crontab -l 2>/dev/null >> "$temp_file" || true
    
    # Add new job
Confidence
90% confidence
Finding
crontab crontab -l 2>/

Session Persistence

Medium
Category
Rogue Agent
Content
temp_file=$(mktemp)
    
    # Get current crontab
    local current_crontab
    current_crontab=$(crontab -l 2>/dev/null) || true
    
    if [[ -z "$current_crontab" ]]; then
Confidence
85% confidence
Finding
crontab current_crontab=$(crontab -l 2>/

Session Persistence

Medium
Category
Rogue Agent
Content
macos)
            case "$action" in
                start)
                    sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.cron.plist 2>/dev/null || \
                    log_error "Need sudo to start cron"
                    ;;
                stop)
Confidence
87% confidence
Finding
launchctl load

Session Persistence

Medium
Category
Rogue Agent
Content
macos)
            case "$action" in
                start)
                    sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.cron.plist 2>/dev/null || \
                    log_error "Need sudo to start cron"
                    ;;
                stop)
Confidence
87% confidence
Finding
plist

VirusTotal

65/65 vendors flagged this skill as clean.

View on VirusTotal