fix: mediapool: block dangerous extensions in any filename segment#6538
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isAllowedExtension only rejected a blocked extension when it was the terminal extension or the segment directly before it (*.php.<ext>). Filenames with a blocked extension as a non-terminal segment in a chain of three or more, e.g. shell.php.any.jpg, slipped through and could be executed as PHP on web servers that map handlers via a multi-extension match (mod_mime AddHandler / non-anchored FilesMatch). Check each dot-separated segment against the blocked list instead. This matches whole segments, so it still allows foo.json and js_datei.txt (no false positive), while also fixing a case-sensitivity gap in the previous str_ends_with check (it ran against the raw filename). Regression introduced in 9d00869 (#6213).
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isAllowedExtension only rejected a blocked extension when it was the terminal extension or the segment directly before it (*.php.). Filenames with a blocked extension as a non-terminal segment in a chain of three or more, e.g. shell.php.any.jpg, slipped through and could be executed as PHP on web servers that map handlers via a multi-extension match (mod_mime AddHandler / non-anchored FilesMatch).
Check each dot-separated segment against the blocked list instead. This matches whole segments, so it still allows foo.json and js_datei.txt (no false positive), while also fixing a case-sensitivity gap in the previous str_ends_with check (it ran against the raw filename).
Regression introduced in 9d00869 (#6213).