SD-005 — World-Writable Permissions
SD-005 flags a chmod in a skill that grants write access to every account on the machine — 777 and its relatives, or an a+w / o+w mode.
What it matches
Permission bits granting write access to everyone — chmod 777 and equivalents.
Why it matters
Anything world-writable can be replaced by any other account or process on the host. If the target is a script the skill or the agent later runs, that is a handoff of execution to whoever edits it first; if it is a config or data file, nothing that reads it afterwards can trust its contents. On a shared machine, or on a host running any other service under its own user, this turns a local presence into the ability to act as you.
Example
bash
# Setup step in SKILL.md: chmod 777 ./scripts/postprocess.sh chmod a+w ~/.cache/example-tool
Both modes let any account on the machine rewrite the file before it is next read or run.
How to fix it
Grant the narrowest mode that works — 700 for a script only you run, 600 for a data file — and fix ownership rather than widening permissions. A permission error during setup is almost always a wrong owner or a wrong directory, not a reason to open the file to everyone.
Known false positives
A permissions example inside a troubleshooting section.
Standards mapping
Prevalence
Pattern SD-005 was detected in 6 of 16475 public skills scanned as of 11 September 2026.
current ruleset 2414c32f04000b5d
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