[fix] escape shell metachars in chdir: to prevent injection - #9451
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headius merged 1 commit intoJun 11, 2026
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PopenExecutor constructs a "cd '<dir>'; ..." for the chdir: option in
spawn/system/IO.popen; the directory path was embedded in single quotes
without escaping, allowing single-quote breakout and arbitrary command
injection:
system('echo hello', chdir: "x'; touch /tmp/pwned; echo '")
MRI uses the POSIX chdir syscall directly and is not affected
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PopenExecutor constructs a cd '<dir>'; ... for the chdir: option in spawn/system/IO.popen;
directory path was embedded in single quotes without escaping, allowing single-quote breakout command injection:
system('echo hello', chdir: "x'; touch /tmp/pwned; echo '")p.s. MRI uses the POSIX chdir syscall directly and is not affected