check_admin_referer( int|string $action = -1, string $query_arg = '_wpnonce' )
Ensures intent by verifying that a user was referred from another admin page with the correct security nonce.
Description
This function ensures the user intends to perform a given action, which helps protect against clickjacking style attacks. It verifies intent, not authorisation, therefore it does not verify the user’s capabilities. This should be performed with current_user_can()
or similar.
If the nonce value is invalid, the function will exit with an "Are You Sure?" style message.
Parameters
- $action
-
(int|string) (Optional) The nonce action.
Default value: -1
- $query_arg
-
(string) (Optional) Key to check for nonce in
$_REQUEST
.Default value: '_wpnonce'
Return
(int|false) 1 if the nonce is valid and generated between 0-12 hours ago, 2 if the nonce is valid and generated between 12-24 hours ago. False if the nonce is invalid.
More Information
- Using the function without the
$action
argument is obsolete and, as of Version 3.2, ifWP_DEBUG
is set totrue
, the function will die with an appropriate message (“You should specify a nonce action to be verified by using the first parameter.” is the default). - As of 2.0.1, the referer is checked only if the
$action
argument is not specified (or set to the default -1) as a backward compatibility fallback for not using a nonce. A nonce is prefered to unreliable referers and with$action
specified the function behaves the same way as wp_verify_nonce() except that it dies after calling wp_nonce_ays() if the nonce is not valid or was not sent.
Source
File: wp-includes/pluggable.php
function check_admin_referer( $action = -1, $query_arg = '_wpnonce' ) { if ( -1 === $action ) { _doing_it_wrong( __FUNCTION__, __( 'You should specify an action to be verified by using the first parameter.' ), '3.2.0' ); } $adminurl = strtolower( admin_url() ); $referer = strtolower( wp_get_referer() ); $result = isset( $_REQUEST[ $query_arg ] ) ? wp_verify_nonce( $_REQUEST[ $query_arg ], $action ) : false; /** * Fires once the admin request has been validated or not. * * @since 1.5.1 * * @param string $action The nonce action. * @param false|int $result False if the nonce is invalid, 1 if the nonce is valid and generated between * 0-12 hours ago, 2 if the nonce is valid and generated between 12-24 hours ago. */ do_action( 'check_admin_referer', $action, $result ); if ( ! $result && ! ( -1 === $action && strpos( $referer, $adminurl ) === 0 ) ) { wp_nonce_ays( $action ); die(); } return $result; }
Changelog
Version | Description |
---|---|
2.5.0 | The $query_arg parameter was added. |
1.2.0 | Introduced. |
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Licensed under the GNU GPLv2+ License.
https://developer.wordpress.org/reference/functions/check_admin_referer