Bug #68773 [Opn->Nab]: basename function does not check non-minimum UTF-8 forms

Edit report at https://bugs.php.net/bug.php?id=68773&edit=1 ID: 68773 Updated by: cmb@php.net Reported by: php at tokumaru dot org Summary: basename function does not check non-minimum UTF-8 forms -Status: Open +Status: Not a bug Type: Bug Package: Filesystem function related Operating System: Ubuntu PHP Version: 5.6.4 Block user comment: N Private report: N New Comment: Sorry, but your problem does not imply a bug in PHP itself. For a list of more appropriate places to ask for help using PHP, please visit http://www.php.net/support.php as this bug system is not the appropriate forum for asking support questions. Due to the volume of reports we can not explain in detail here why your report is not a bug. The support channels will be able to provide an explanation for you. Thank you for your interest in PHP. basename() is supposed to strip away leading path components, but not to validate/sanitize the given parameter. Previous Comments: ------------------------------------------------------------------------ [2015-01-09 06:21:11] php at tokumaru dot org Description: ------------ Function basename does not check invalid multibyte strings. For example, non-minimum UTF-8 forms are treated as normal file names. This is a potential path-traversal vulnerability like CVE-2008-2938. Test script: --------------- setlocale('LC_CTYPE', 'en_US.utf8'); var_dump(bin2hex(basename("..\xC0\xAFx"))); // \xC0\xAF is a non-minimum UTF-8 form of '/' Expected result: ---------------- string(2) "78" OR string(0) "" Actual result: -------------- string(10) "2e2ec0af78" ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=68773&edit=1