GHSA-g3hq-hphg-8fhh

### Summary pheditor's terminal feature restricts callers to an allowlist of commands (`TERMINAL_COMMANDS`) and rejects shell metacharacters. The allowlist is enforced as a PREFIX match with no argument validation, and the allowlist includes binaries that grant arbitrary command execution through their own options (`find`, `git`, `php`, `tar`, `grep`). A caller can therefore run any command using only allowlisted binaries and no rejected metacharacter, escaping the allowlist restriction the terminal feature relies on. ### Relationship to the prior terminal advisories (this is a surviving, distinct vector) The prior terminal advisories were all shell-metacharacter injections: GHSA-9643-6xjp-vx57 (`$()`), GHSA-wg4w-wr5q-6vjc (`|`, backtick, newline), GHSA-jvc5-58fv-w8cq (`;` via the dir field). The current code rejects those characters. This report is a different class — CWE-88 argument injection through an allowlisted binary's flags — which the metacharacter denylist does not address. ### Root cause (HEAD, v2.0.6) In the `terminal` action handler of `pheditor.php`: 1. `:588` rejects `&`, `;`, `|`, `$`, backtick, `\n`, `\r`. It does NOT reject space, `-`, `{`, `}`, `+`, `/`, `.`. 2. `:595-605` checks the command against `TERMINAL_COMMANDS` (defined `:25`: `ls,...,php,...,git,find,grep,...,tar,...,composer,exit`) using a PREFIX match: `strlen($command) >= strlen($value) && substr($command, 0, strlen($value)) == $value`. There is no word boundary and no validation of the arguments that follow. 3. `:617` runs the command through the shell unchanged: `shell_exec((empty($dir) ? null : 'cd ' . escapeshellarg($dir) . ' && ') . $command . ' && echo \ ; pwd')`. So a command beginning with an allowlisted binary, carrying a code-exec flag, and containing none of the rejected characters reaches `shell_exec` intact. ### Proof of concept (reproduced) POST to the terminal action with: command = `find . -maxdepth 0 -exec touch /tmp/PWNED {} +` dir = (any) This contains n