The SessionStart nudge built a statusLine command by interpolating the
plugin's __dirname path into a double-quoted shell string. A clone path
containing shell metacharacters (quotes, &, $, backtick, ;) could break
out when the suggested command later runs via the statusline shell.
Low severity in practice: the path is the install location, so triggering
it requires installing into a maliciously-named directory, i.e. the
attacker already controls the filesystem. Hardening it anyway.
Gate the snippet behind isShellSafe() (allowlist of ordinary path chars,
allowing : \ / for normal Windows and POSIX paths). Unsafe paths fall
back to a manual-setup instruction instead of an embeddable command. An
allowlist beats a per-shell escaper, which is its own edge-case bug farm.
Refs #200
Issue #34 made the hooks honor CLAUDE_CONFIG_DIR when writing the mode flag
($CLAUDE_CONFIG_DIR/.ponytail-active), enforced by tests/hooks.test.js. But
both statusline scripts still hardcoded $HOME/.claude/.ponytail-active, so any
user with CLAUDE_CONFIG_DIR set gets no badge — or a stale mode from a
pre-migration ~/.claude flag that never updates again.
Make both scripts resolve the flag the same way getClaudeDir() does: prefer
CLAUDE_CONFIG_DIR, fall back to ~/.claude. The fallback branch is identical to
the previous behavior, so unset-env users are unaffected. Also corrects the
now-inaccurate path comment in the activation hook header.
The final writeHookOutput('SessionStart', ...) call was the only operation
in the file outside a try/catch. writeHookOutput ends in a bare
process.stdout.write, so a closed stdout / broken pipe (EPIPE) at hook exit
throws uncaught and crashes the hook with a non-zero exit code. Wrap it to
match the file's existing never-block-session-start posture.
settings.json written by Notepad or VS Code on Windows can carry a
UTF-8 BOM. JSON.parse then throws SyntaxError, the outer catch swallows
it, hasStatusline stays false, and the statusline setup nudge is never
emitted.
Strip the leading BOM before parsing, matching the existing handling in
ponytail-mode-tracker.js. (#96 added a null guard but not BOM stripping.)
ponytail-activate.js and ponytail-runtime.js hardcoded ~/.claude for the
flag file and settings lookup, ignoring CLAUDE_CONFIG_DIR. Add a shared
getClaudeDir() to ponytail-config.js and use it in both. Regression test
added to hooks.test.js.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Hardening per the A-F benchmark brief: non-trivial logic leaves one
runnable check; ponytail: comments on ceiling-bearing shortcuts name
the ceiling and upgrade path; prefer the edge-case-correct stdlib
option at equal size. Applied to SKILL.md, all cross-agent rule
copies, the hook fallback, and a guard line in ponytail-review.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
v1 lost to caveman on tokens/time despite minimal code: it wrote
essays defending each simplification. v2 caps explanation at three
lines and ships the lazy version instead of stalling on necessity
questions. Benchmark: 136.6k tok vs caveman 138.4k, code 47 vs 117
lines across 5 tasks.
DietrichGebert