T05 · Unauthorized Access and Privilege Escalation
Warning
- Location
- SKILL.md:26
- Finding
- Default Diagnostic Workflow Requests Excessive Privileged System Access<![CDATA[ ## Vulnerability Details **File Location**: `SKILL.md:26-50` **Vulnerability Type**: Excessive privileged access during cron diagnostics **Risk Level**: Medium ### Vulnerable Code ```bash ### 1. List All Jobs ```bash # List user's crontab crontab -l # List system crontabs sudo cat /etc/crontab ls -la /etc/cron.d/ ``` ### 2. Check Recent Execution ```bash # Check cron logs (location varies by system) # Debian/Ubuntu: grep CRON /var/log/syslog | tail -50 # RHEL/CentOS: tail -50 /var/log/cron # macOS: log show --predicate 'process == "cron"' --last 1h # Check for specific job output grep "your_job_name" /var/log/syslog | tail -20 ``` ``` ### Technical Analysis The Skill instructs an agent to enumerate system-wide cron configuration and inspect operating-system logs as part of its default diagnostic workflow. In particular, `sudo cat /etc/crontab` explicitly requests elevated access. This exceeds least privilege when the user only needs diagnosis of their own crontab or a specific scheduled job. System cron definitions and logs may reveal usernames, internal filesystem paths, command arguments, execution schedules, infrastructure details, and potentially secrets that operators have improperly embedded in command lines. The later instruction to write a health report can propagate this information into `~/workspace/reports/cron-health-YYYY-MM-DD.md`. The behavior is related to cron administration but does not install persistence. The pre-scan persistence warning is therefore a false positive: the Skill lists existing scheduled tasks and does not create or modify crontabs, services, startup hooks, or scheduled jobs. ### Attack Path 1. A user requests a routine health check for a personal or specific cron job. 2. The agent follows the unconditional “List All Jobs” workflow. 3. The agent executes `crontab -l`, then requests or uses `sudo` to read `/etc/crontab` and attempts to inspect `/etc/cron.d/`. 4. The agent reads broad system cron logs rat ...[truncated 1233 chars]
- Remediation
- <![CDATA[ ## Remediation Suggestions 1. Default to user-scoped inspection with `crontab -l`. 2. Ask for explicit confirmation before reading system-wide cron definitions or invoking `sudo`. 3. Explain which files and logs will be accessed and why elevated access is necessary. 4. Only escalate after user-level inspection is insufficient or when the user explicitly requests a system-wide audit. 5. Restrict log searches to the named job, relevant user, and narrowest practical time range. 6. Avoid reading complete system cron files when targeted metadata or user-supplied configuration is sufficient. 7. Redact credentials, tokens, command arguments, usernames, and sensitive paths before placing findings in agent context or reports. 8. Warn the user before writing privileged operational information to `~/workspace/reports/`. 9. Replace the default workflow with a staged approach such as: ```bash # Stage 1: user-scoped inspection crontab -l # Stage 2: run only after explicit approval and demonstrated need sudo cat /etc/crontab ls -la /etc/cron.d/ ``` 10. Document clearly that system-level inspection is optional and may expose information about unrelated users and services. ]]>