Description:
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safe_mode bypass with a preceding backslash. tested with exec(), system() and passthru(). on windows only.

Sorry, I do feel this bug concerns a security issue but I got no response from security@php.net after sending 2 emails from 2 different accounts about 6 weeks ago.

Reproduce code:
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on commandline:
php -n -d safe_mode=on -r "exec('\ping 192.168.222.1');"

with PHP script and enabled safe_mode in php.ini:
<? exec('\ping 192.168.222.1'); ?>

Expected result:
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safe_mode turned on should block code execution from exec() and other functions.

Actual result:
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By adding a backslash infront of the command the command got  executed anyhow.