Bug #64430 [Com]: strip_tags() clobbers non-tag entities

Edit report at https://bugs.php.net/bug.php?id=64430&edit=1 ID: 64430 Comment by: gdataonline at gmail dot com Reported by: gdataonline at gmail dot com Summary: strip_tags() clobbers non-tag entities Status: Open Type: Bug Package: Unknown/Other Function Operating System: Windows 7 x64 PHP Version: 5.4.13 Block user comment: N Private report: N New Comment: I'm starting to suspect that strip_tags treats anything that matches <[^>\s]*> as an HTML tag, regardless of where it appears or if it's valid HTML. Previous Comments: ------------------------------------------------------------------------ [2013-03-15 15:15:58] gdataonline at gmail dot com Description: ------------ strip_tags() will clobber all remaining input after encountering non-HTML tags, regardless if embedded in "allowable-tags". When strip_tags() encounters a "<" followed by *any non-whitespace*, it assumes it's an HTML tag, even if it couldn't legally be one. In the example below, even something as simple as a "<=" appearing in JavaScript is enough to trigger the behavior. For a full list of characters that strip_tags() clobbers on, see this example: http://ideone.com/BEPINI Test script: --------------- <?php // Example 1: Without <= $code = "<script>if (foo >= bar){ alert(0); }</script>"; var_dump(strip_tags($code)); var_dump(strip_tags($code, "<script>")); // Example 2: With <= $code = "<script>if (foo <= bar){ alert(0); }</script>"; var_dump(strip_tags($code)); var_dump(strip_tags($code, "<script>")); ?> Expected result: ---------------- string(28) "if (foo >= bar){ alert(0); }" string(45) "<script>if (foo >= bar){ alert(0); }</script>" string(28) "if (foo <= bar){ alert(0); }" string(45) "<script>if (foo <= bar){ alert(0); }</script>" Actual result: -------------- string(28) "if (foo >= bar){ alert(0); }" string(45) "<script>if (foo >= bar){ alert(0); }</script>" string(8) "if (foo " string(16) "<script>if (foo " ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=64430&edit=1