Since I use GIT to preserve all my sites, including those in WP, I realized what they did. Maybe the Mime header of the file you are uploading is not exactly “image/svg+xml” (mine was). You can force every file by replacing with:
if (true || $real_mime !== $type ) {
This is VERY BAD, but it will work in the meanwhile if you are the only one working in your site, or you can inspect the contents of $real_mime and add the exception like I did before.
FILE DIFF in 4.7.1:
diff –git a/wp-includes/functions.php b/wp-includes/functions.php
index 8593e8c..2ae482f 100755
— a/wp-includes/functions.php
+++ b/wp-includes/functions.php
@@ -2254,7 +2254,7 @@ function wp_check_filetype( $filename, $mimes = null ) {
* If it’s determined that the extension does not match the file’s real type,
* then the “proper_filename” value will be set with a proper filename and extension.
*
– * Currently this function only supports validating images known to getimagesize().
+ * Currently this function only supports renaming images validated via wp_get_image_mime().
*
* @since 3.0.0
*
@@ -2278,14 +2278,15 @@ function wp_check_filetype_and_ext( $file, $filename, $mimes = null ) {
return compact( ‘ext’, ‘type’, ‘proper_filename’ );
}
– // We’re able to validate images using GD
– if ( $type && 0 === strpos( $type, ‘image/’ ) && function_exists(‘getimagesize’) ) {
+ // Validate image types.
+ if ( $type && 0 === strpos( $type, ‘image/’ ) ) {
// Attempt to figure out what type of image it actually is
– $imgstats = @getimagesize( $file );
+ $real_mime = wp_get_image_mime( $file );
– // If getimagesize() knows what kind of image it really is and if the real MIME doesn’t match the claimed MIME
– if ( !empty($imgstats[‘mime’]) && $imgstats[‘mime’] != $type ) {
+ if ( ! $real_mime ) {
+ $type = $ext = false;
+ } elseif ( $real_mime != $type ) {
/**
* Filters the list mapping image mime types to their respective extensions.
*
@@ -2302,10 +2303,10 @@ function wp_check_filetype_and_ext( $file, $filename, $mimes = null ) {
) );
// Replace whatever is after the last period in the filename with the correct extension
– if ( ! empty( $mime_to_ext[ $imgstats[‘mime’] ] ) ) {
+ if ( ! empty( $mime_to_ext[ $real_mime ] ) ) {
$filename_parts = explode( ‘.’, $filename );
array_pop( $filename_parts );
– $filename_parts[] = $mime_to_ext[ $imgstats[‘mime’] ];
+ $filename_parts[] = $mime_to_ext[ $real_mime ];
$new_filename = implode( ‘.’, $filename_parts );
if ( $new_filename != $filename ) {
@@ -2315,8 +2316,20 @@ function wp_check_filetype_and_ext( $file, $filename, $mimes = null ) {
$wp_filetype = wp_check_filetype( $new_filename, $mimes );
$ext = $wp_filetype[‘ext’];
$type = $wp_filetype[‘type’];
+ } else {
+ $type = $ext = false;
}
}
+ } elseif ( function_exists( ‘finfo_file’ ) ) {
+ // Use finfo_file if available to validate non-image files.
+ $finfo = finfo_open( FILEINFO_MIME_TYPE );
+ $real_mime = finfo_file( $finfo, $file );
+ finfo_close( $finfo );
+
+ // If the extension does not match the file’s real type, return false.
+ if ($real_mime != ‘image/svg+xml’ && $real_mime !== $type ) {
+ $type = $ext = false;
+ }
}
/**
@@ -2335,6 +2348,38 @@ function wp_check_filetype_and_ext( $file, $filename, $mimes = null ) {
}
/**
+ * Returns the real mime type of an image file.
+ *
+ * This depends on exif_imagetype() or getimagesize() to determine real mime types.
+ *
+ * @since 4.7.1
+ *
+ * @param string $file Full path to the file.
+ * @return string|false The actual mime type or false if the type cannot be determined.
+ */
+function wp_get_image_mime( $file ) {
+ /*
+ * Use exif_imagetype() to check the mimetype if available or fall back to
+ * getimagesize() if exif isn’t avaialbe. If either function throws an Exception
+ * we assume the file could not be validated.
+ */
+ try {
+ if ( is_callable( ‘exif_imagetype’ ) ) {
+ $mime = image_type_to_mime_type( exif_imagetype( $file ) );
+ } elseif ( function_exists( ‘getimagesize’ ) ) {
+ $imagesize = getimagesize( $file );
+ $mime = ( isset( $imagesize[‘mime’] ) ) ? $imagesize[‘mime’] : false;
+ } else {
+ $mime = false;
+ }
+ } catch ( Exception $e ) {
+ $mime = false;
+ }
+
+ return $mime;
+}
+
+/**
* Retrieve list of mime types and file extensions.
*
* @since 3.5.0
