diff --git a/wp-admin/about.php b/wp-admin/about.php
index 7a8295658f91a5cd76fe45637d7b3b1d3de1e997..bcefac9f853f7a04947e72190e67aeaf551378e2 100644
--- a/wp-admin/about.php
+++ b/wp-admin/about.php
@@ -45,6 +45,9 @@ include( ABSPATH . 'wp-admin/admin-header.php' );
<div class="changelog point-releases">
<h3><?php _e( 'Maintenance and Security Releases' ); ?></h3>
+ <p><?php printf( __( '<strong>Version %s</strong> addressed one security issue.' ), '4.8.3' ); ?>
+ <?php printf( __( 'For more information, see <a href="%s">the release notes</a>.' ), 'https://codex.wordpress.org/Version_4.8.3' ); ?>
+ </p>
<p><?php printf( _n( '<strong>Version %1$s</strong> addressed some security issues and fixed %2$s bug.',
'<strong>Version %1$s</strong> addressed some security issues and fixed %2$s bugs.', 5 ), '4.8.2', number_format_i18n( 5 ) ); ?>
<?php printf( __( 'For more information, see <a href="%s">the release notes</a>.' ), 'https://codex.wordpress.org/Version_4.8.2' ); ?>
diff --git a/wp-includes/formatting.php b/wp-includes/formatting.php
index 9e5f8b4147de7ead89a2d77e6fec2f04daae232b..2a88509fcaf2b70f615434d4cee83eb22ecab785 100644
--- a/wp-includes/formatting.php
+++ b/wp-includes/formatting.php
@@ -3738,6 +3738,11 @@ function _deep_replace( $search, $subject ) {
* Sometimes, spot-escaping is required or useful. One example
* is preparing an array for use in an IN clause.
*
+ * NOTE: Since 4.8.3, '%' characters will be replaced with a placeholder string,
+ * this prevents certain SQLi attacks from taking place. This change in behaviour
+ * may cause issues for code that expects the return value of esc_sql() to be useable
+ * for other purposes.
+ *
* @since 2.8.0
*
* @global wpdb $wpdb WordPress database abstraction object.
diff --git a/wp-includes/post.php b/wp-includes/post.php
index 0d624006d7ad768908f900ef91b0724a061560d4..c39939629f7a286b1bc7709566cd1d5f3cda34e1 100644
--- a/wp-includes/post.php
+++ b/wp-includes/post.php
@@ -4246,10 +4246,10 @@ function get_page_by_path( $page_path, $output = OBJECT, $post_type = 'page' ) {
$page_path = str_replace('%2F', '/', $page_path);
$page_path = str_replace('%20', ' ', $page_path);
$parts = explode( '/', trim( $page_path, '/' ) );
- $parts = esc_sql( $parts );
$parts = array_map( 'sanitize_title_for_query', $parts );
+ $escaped_parts = esc_sql( $parts );
- $in_string = "'" . implode( "','", $parts ) . "'";
+ $in_string = "'" . implode( "','", $escaped_parts ) . "'";
if ( is_array( $post_type ) ) {
$post_types = $post_type;
diff --git a/wp-includes/version.php b/wp-includes/version.php
index db4e8779c17b82b238e502b154a602eb2d06a967..ff2d4d6cd708a8ae12fcfc2127ed6a97c2fa23c7 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
*
* @global string $wp_version
*/
-$wp_version = '4.8.2';
+$wp_version = '4.8.3';
/**
* Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.
diff --git a/wp-includes/wp-db.php b/wp-includes/wp-db.php
index ced76bd86739ecb1d96bf7fe07e4b0c201b3bb1a..553cd39d9fd91fad066fe8622bd29abcac69692a 100644
--- a/wp-includes/wp-db.php
+++ b/wp-includes/wp-db.php
@@ -1168,20 +1168,22 @@ class wpdb {
function _real_escape( $string ) {
if ( $this->dbh ) {
if ( $this->use_mysqli ) {
- return mysqli_real_escape_string( $this->dbh, $string );
+ $escaped = mysqli_real_escape_string( $this->dbh, $string );
} else {
- return mysql_real_escape_string( $string, $this->dbh );
+ $escaped = mysql_real_escape_string( $string, $this->dbh );
}
- }
-
- $class = get_class( $this );
- if ( function_exists( '__' ) ) {
- /* translators: %s: database access abstraction class, usually wpdb or a class extending wpdb */
- _doing_it_wrong( $class, sprintf( __( '%s must set a database connection for use with escaping.' ), $class ), '3.6.0' );
} else {
- _doing_it_wrong( $class, sprintf( '%s must set a database connection for use with escaping.', $class ), '3.6.0' );
+ $class = get_class( $this );
+ if ( function_exists( '__' ) ) {
+ /* translators: %s: database access abstraction class, usually wpdb or a class extending wpdb */
+ _doing_it_wrong( $class, sprintf( __( '%s must set a database connection for use with escaping.' ), $class ), '3.6.0' );
+ } else {
+ _doing_it_wrong( $class, sprintf( '%s must set a database connection for use with escaping.', $class ), '3.6.0' );
+ }
+ $escaped = addslashes( $string );
}
- return addslashes( $string );
+
+ return $this->add_placeholder_escape( $escaped );
}
/**
@@ -1257,67 +1259,120 @@ class wpdb {
/**
* Prepares a SQL query for safe execution. Uses sprintf()-like syntax.
*
- * The following directives can be used in the query format string:
+ * The following placeholders can be used in the query string:
* %d (integer)
* %f (float)
* %s (string)
- * %% (literal percentage sign - no argument needed)
*
- * All of %d, %f, and %s are to be left unquoted in the query string and they need an argument passed for them.
- * Literals (%) as parts of the query must be properly written as %%.
+ * All placeholders MUST be left unquoted in the query string. A corresponding argument MUST be passed for each placeholder.
*
- * This function only supports a small subset of the sprintf syntax; it only supports %d (integer), %f (float), and %s (string).
- * Does not support sign, padding, alignment, width or precision specifiers.
- * Does not support argument numbering/swapping.
+ * For compatibility with old behavior, numbered or formatted string placeholders (eg, %1$s, %5s) will not have quotes
+ * added by this function, so should be passed with appropriate quotes around them for your usage.
*
- * May be called like {@link https://secure.php.net/sprintf sprintf()} or like {@link https://secure.php.net/vsprintf vsprintf()}.
+ * Literal percentage signs (%) in the query string must be written as %%. Percentage wildcards (for example,
+ * to use in LIKE syntax) must be passed via a substitution argument containing the complete LIKE string, these
+ * cannot be inserted directly in the query string. Also see {@see esc_like()}.
*
- * Both %d and %s should be left unquoted in the query string.
+ * Arguments may be passed as individual arguments to the method, or as a single array containing all arguments. A combination
+ * of the two is not supported.
*
- * $wpdb->prepare( "SELECT * FROM `table` WHERE `column` = %s AND `field` = %d", 'foo', 1337 );
+ * Examples:
+ * $wpdb->prepare( "SELECT * FROM `table` WHERE `column` = %s AND `field` = %d OR `other_field` LIKE %s", array( 'foo', 1337, '%bar' ) );
* $wpdb->prepare( "SELECT DATE_FORMAT(`field`, '%%c') FROM `table` WHERE `column` = %s", 'foo' );
*
* @link https://secure.php.net/sprintf Description of syntax.
* @since 2.3.0
*
* @param string $query Query statement with sprintf()-like placeholders
- * @param array|mixed $args The array of variables to substitute into the query's placeholders if being called like
- * {@link https://secure.php.net/vsprintf vsprintf()}, or the first variable to substitute into the query's placeholders if
- * being called like {@link https://secure.php.net/sprintf sprintf()}.
- * @param mixed $args,... further variables to substitute into the query's placeholders if being called like
- * {@link https://secure.php.net/sprintf sprintf()}.
+ * @param array|mixed $args The array of variables to substitute into the query's placeholders if being called with an array of arguments,
+ * or the first variable to substitute into the query's placeholders if being called with individual arguments.
+ * @param mixed $args,... further variables to substitute into the query's placeholders if being called wih individual arguments.
* @return string|void Sanitized query string, if there is a query to prepare.
*/
public function prepare( $query, $args ) {
- if ( is_null( $query ) )
+ if ( is_null( $query ) ) {
return;
+ }
// This is not meant to be foolproof -- but it will catch obviously incorrect usage.
if ( strpos( $query, '%' ) === false ) {
+ wp_load_translations_early();
_doing_it_wrong( 'wpdb::prepare', sprintf( __( 'The query argument of %s must have a placeholder.' ), 'wpdb::prepare()' ), '3.9.0' );
}
$args = func_get_args();
array_shift( $args );
- // If args were passed as an array (as in vsprintf), move them up
+ // If args were passed as an array (as in vsprintf), move them up.
+ $passed_as_array = false;
if ( is_array( $args[0] ) && count( $args ) == 1 ) {
+ $passed_as_array = true;
$args = $args[0];
}
foreach ( $args as $arg ) {
if ( ! is_scalar( $arg ) && ! is_null( $arg ) ) {
- _doing_it_wrong( 'wpdb::prepare', sprintf( 'Unsupported value type (%s).', gettype( $arg ) ), '4.8.2' );
+ wp_load_translations_early();
+ _doing_it_wrong( 'wpdb::prepare', sprintf( __( 'Unsupported value type (%s).' ), gettype( $arg ) ), '4.8.2' );
+ }
+ }
+
+ /*
+ * Specify the formatting allowed in a placeholder. The following are allowed:
+ *
+ * - Sign specifier. eg, $+d
+ * - Numbered placeholders. eg, %1$s
+ * - Padding specifier, including custom padding characters. eg, %05s, %'#5s
+ * - Alignment specifier. eg, %05-s
+ * - Precision specifier. eg, %.2f
+ */
+ $allowed_format = '(?:[1-9][0-9]*[$])?[-+0-9]*(?: |0|\'.)?[-+0-9]*(?:\.[0-9]+)?';
+
+ /*
+ * If a %s placeholder already has quotes around it, removing the existing quotes and re-inserting them
+ * ensures the quotes are consistent.
+ *
+ * For backwards compatibility, this is only applied to %s, and not to placeholders like %1$s, which are frequently
+ * used in the middle of longer strings, or as table name placeholders.
+ */
+ $query = str_replace( "'%s'", '%s', $query ); // Strip any existing single quotes.
+ $query = str_replace( '"%s"', '%s', $query ); // Strip any existing double quotes.
+ $query = preg_replace( '/(?<!%)%s/', "'%s'", $query ); // Quote the strings, avoiding escaped strings like %%s.
+
+ $query = preg_replace( "/(?<!%)(%($allowed_format)?f)/" , '%\\2F', $query ); // Force floats to be locale unaware.
+
+ $query = preg_replace( "/%(?:%|$|(?!($allowed_format)?[sdF]))/", '%%\\1', $query ); // Escape any unescaped percents.
+
+ // Count the number of valid placeholders in the query.
+ $placeholders = preg_match_all( "/(^|[^%]|(%%)+)%($allowed_format)?[sdF]/", $query, $matches );
+
+ if ( count( $args ) !== $placeholders ) {
+ if ( 1 === $placeholders && $passed_as_array ) {
+ // If the passed query only expected one argument, but the wrong number of arguments were sent as an array, bail.
+ wp_load_translations_early();
+ _doing_it_wrong( 'wpdb::prepare', __( 'The query only expected one placeholder, but an array of multiple placeholders was sent.' ), '4.9.0' );
+
+ return;
+ } else {
+ /*
+ * If we don't have the right number of placeholders, but they were passed as individual arguments,
+ * or we were expecting multiple arguments in an array, throw a warning.
+ */
+ wp_load_translations_early();
+ _doing_it_wrong( 'wpdb::prepare',
+ /* translators: 1: number of placeholders, 2: number of arguments passed */
+ sprintf( __( 'The query does not contain the correct number of placeholders (%1$d) for the number of arguments passed (%2$d).' ),
+ $placeholders,
+ count( $args ) ),
+ '4.8.3'
+ );
}
}
- $query = str_replace( "'%s'", '%s', $query ); // in case someone mistakenly already singlequoted it
- $query = str_replace( '"%s"', '%s', $query ); // doublequote unquoting
- $query = preg_replace( '|(?<!%)%f|' , '%F', $query ); // Force floats to be locale unaware
- $query = preg_replace( '|(?<!%)%s|', "'%s'", $query ); // quote the strings, avoiding escaped strings like %%s
- $query = preg_replace( '/%(?:%|$|([^dsF]))/', '%%\\1', $query ); // escape any unescaped percents
array_walk( $args, array( $this, 'escape_by_ref' ) );
- return @vsprintf( $query, $args );
+ $query = @vsprintf( $query, $args );
+
+ return $this->add_placeholder_escape( $query );
}
/**
@@ -1895,6 +1950,64 @@ class wpdb {
}
}
+ /**
+ * Generates and returns a placeholder escape string for use in queries returned by ::prepare().
+ *
+ * @since 4.8.3
+ *
+ * @return string String to escape placeholders.
+ */
+ public function placeholder_escape() {
+ static $placeholder;
+
+ if ( ! $placeholder ) {
+ // If ext/hash is not present, compat.php's hash_hmac() does not support sha256.
+ $algo = function_exists( 'hash' ) ? 'sha256' : 'sha1';
+ // Old WP installs may not have AUTH_SALT defined.
+ $salt = defined( 'AUTH_SALT' ) ? AUTH_SALT : rand();
+
+ $placeholder = '{' . hash_hmac( $algo, uniqid( $salt, true ), $salt ) . '}';
+ }
+
+ /*
+ * Add the filter to remove the placeholder escaper. Uses priority 0, so that anything
+ * else attached to this filter will recieve the query with the placeholder string removed.
+ */
+ if ( ! has_filter( 'query', array( $this, 'remove_placeholder_escape' ) ) ) {
+ add_filter( 'query', array( $this, 'remove_placeholder_escape' ), 0 );
+ }
+
+ return $placeholder;
+ }
+
+ /**
+ * Adds a placeholder escape string, to escape anything that resembles a printf() placeholder.
+ *
+ * @since 4.8.3
+ *
+ * @param string $query The query to escape.
+ * @return string The query with the placeholder escape string inserted where necessary.
+ */
+ public function add_placeholder_escape( $query ) {
+ /*
+ * To prevent returning anything that even vaguely resembles a placeholder,
+ * we clobber every % we can find.
+ */
+ return str_replace( '%', $this->placeholder_escape(), $query );
+ }
+
+ /**
+ * Removes the placeholder escape strings from a query.
+ *
+ * @since 4.8.3
+ *
+ * @param string $query The query from which the placeholder will be removed.
+ * @return string The query with the placeholder removed.
+ */
+ public function remove_placeholder_escape( $query ) {
+ return str_replace( $this->placeholder_escape(), '%', $query );
+ }
+
/**
* Insert a row into a table.
*