Skip to content

Administration: Escape custom background page output #12000

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
ArkaPrabhaChowdhury wants to merge 4 commits into
base: trunk
Choose a base branch
from
Draft

Administration: Escape custom background page output #12000

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
ce2c261
Administration: Escape custom background page output
ArkaPrabhaChowdhury May 28, 2026
f3c7256
Administration: Fix custom background PHPCS formatting
ArkaPrabhaChowdhury May 29, 2026
852276e
Build/Test Tools: Skip DB check during local env config creation
ArkaPrabhaChowdhury May 29, 2026
aa83e7a
Revert "Build/Test Tools: Skip DB check during local env config creat…
ArkaPrabhaChowdhury May 29, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
27 changes: 14 additions & 13 deletions src/wp-admin/includes/class-custom-background.php
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -247,7 +247,7 @@ public function admin_page() {
$message = sprintf(
/* translators: %s: URL to background image configuration in Customizer. */
__( 'You can now manage and live-preview Custom Backgrounds in the <a href="%s">Customizer</a>.' ),
admin_url( 'customize.php?autofocus[control]=background_image' )
esc_url( admin_url( 'customize.php?autofocus[control]=background_image' ) )
);
wp_admin_notice(
$message,
Expand Down Expand Up @@ -308,7 +308,7 @@ public function admin_page() {
. " background-attachment: $background_attachment;";
}
?>
<div id="custom-background-image" style="<?php echo $background_styles; ?>"><?php // Must be double quote, see above. ?>
<div id="custom-background-image" style="<?php echo esc_attr( $background_styles ); ?>"><?php // Must be double quote, see above. ?>
<?php if ( $background_image_thumb ) { ?>
<img class="custom-background-image" src="<?php echo $background_image_thumb; ?>" style="visibility:hidden;" alt="" /><br />
<img class="custom-background-image" src="<?php echo $background_image_thumb; ?>" style="visibility:hidden;" alt="" />
Expand Down Expand Up @@ -431,16 +431,16 @@ public function admin_page() {
);
?>
<tr>
<th scope="row"><?php echo $background_position_title; ?></th>
<td><fieldset><legend class="screen-reader-text"><span><?php echo $background_position_title; ?></span></legend>
<th scope="row"><?php echo esc_html( $background_position_title ); ?></th>
<td><fieldset><legend class="screen-reader-text"><span><?php echo esc_html( $background_position_title ); ?></span></legend>
<div class="background-position-control">
<?php foreach ( $background_position_options as $group ) : ?>
<div class="button-group">
<?php foreach ( $group as $value => $input ) : ?>
<label>
<input class="ui-helper-hidden-accessible" name="background-position" type="radio" value="<?php echo esc_attr( $value ); ?>"<?php checked( $value, $background_position ); ?>>
<span class="button display-options position"><span class="<?php echo esc_attr( $input['icon'] ); ?>" aria-hidden="true"></span></span>
<span class="screen-reader-text"><?php echo $input['label']; ?></span>
<span class="screen-reader-text"><?php echo esc_html( $input['label'] ); ?></span>
</label>
<?php endforeach; ?>
</div>
Expand All @@ -451,8 +451,8 @@ public function admin_page() {

<?php $image_size_title = __( 'Image Size' ); ?>
<tr>
<th scope="row"><label for="background-size"><?php echo $image_size_title; ?></label></th>
<td><fieldset><legend class="screen-reader-text"><span><?php echo $image_size_title; ?></span></legend>
<th scope="row"><label for="background-size"><?php echo esc_html( $image_size_title ); ?></label></th>
<td><fieldset><legend class="screen-reader-text"><span><?php echo esc_html( $image_size_title ); ?></span></legend>
<select id="background-size" name="background-size">
<option value="auto"<?php selected( 'auto', get_theme_mod( 'background_size', get_theme_support( 'custom-background', 'default-size' ) ) ); ?>><?php _ex( 'Original', 'Original Size' ); ?></option>
<option value="contain"<?php selected( 'contain', get_theme_mod( 'background_size', get_theme_support( 'custom-background', 'default-size' ) ) ); ?>><?php _e( 'Fit to Screen' ); ?></option>
Expand All @@ -463,17 +463,17 @@ public function admin_page() {

<?php $background_repeat_title = _x( 'Repeat', 'Background Repeat' ); ?>
<tr>
<th scope="row"><?php echo $background_repeat_title; ?></th>
<td><fieldset><legend class="screen-reader-text"><span><?php echo $background_repeat_title; ?></span></legend>
<th scope="row"><?php echo esc_html( $background_repeat_title ); ?></th>
<td><fieldset><legend class="screen-reader-text"><span><?php echo esc_html( $background_repeat_title ); ?></span></legend>
<input name="background-repeat" type="hidden" value="no-repeat">
<label><input type="checkbox" name="background-repeat" value="repeat"<?php checked( 'repeat', get_theme_mod( 'background_repeat', get_theme_support( 'custom-background', 'default-repeat' ) ) ); ?>> <?php _e( 'Repeat Background Image' ); ?></label>
</fieldset></td>
</tr>

<?php $background_scroll_title = _x( 'Scroll', 'Background Scroll' ); ?>
<tr>
<th scope="row"><?php echo $background_scroll_title; ?></th>
<td><fieldset><legend class="screen-reader-text"><span><?php echo $background_scroll_title; ?></span></legend>
<th scope="row"><?php echo esc_html( $background_scroll_title ); ?></th>
<td><fieldset><legend class="screen-reader-text"><span><?php echo esc_html( $background_scroll_title ); ?></span></legend>
<input name="background-attachment" type="hidden" value="fixed">
<label><input name="background-attachment" type="checkbox" value="scroll" <?php checked( 'scroll', get_theme_mod( 'background_attachment', get_theme_support( 'custom-background', 'default-attachment' ) ) ); ?>> <?php _e( 'Scroll with Page' ); ?></label>
</fieldset></td>
Expand All @@ -487,10 +487,11 @@ public function admin_page() {
<?php
$default_color = '';
if ( current_theme_supports( 'custom-background', 'default-color' ) ) {
$default_color = ' data-default-color="#' . esc_attr( get_theme_support( 'custom-background', 'default-color' ) ) . '"';
$default_color = get_theme_support( 'custom-background', 'default-color' );
}
?>
<input type="text" name="background-color" id="background-color" value="#<?php echo esc_attr( get_background_color() ); ?>"<?php echo $default_color; ?>>
<input type="text" name="background-color" id="background-color" value="#<?php echo esc_attr( get_background_color() ); ?>"<?php if ( $default_color ) : ?>
data-default-color="#<?php echo esc_attr( $default_color ); ?>"<?php endif; ?>>
</fieldset></td>
</tr>
</tbody>
Expand Down
88 changes: 88 additions & 0 deletions tests/phpunit/tests/admin/customBackground.php
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,88 @@
<?php
/**
* @group admin
* @group themes
*/

require_once ABSPATH . 'wp-admin/includes/class-custom-background.php';

class Tests_Admin_CustomBackground extends WP_UnitTestCase {
/**
* Administrator user ID.
*
* @var int
*/
private static $admin_id;

public static function wpSetUpBeforeClass( WP_UnitTest_Factory $factory ) {
self::$admin_id = $factory->user->create(
array(
'role' => 'administrator',
)
);
}

public function set_up() {
parent::set_up();

wp_set_current_user( self::$admin_id );
set_current_screen( 'appearance_page_custom-background' );

remove_theme_support( 'custom-background' );
add_theme_support(
'custom-background',
array(
'default-position-x' => 'left',
'default-position-y' => 'top',
'default-size' => 'auto',
'default-repeat' => 'repeat',
'default-attachment' => 'scroll',
)
);
}

public function tear_down() {
remove_filter( 'theme_mod_background_position_x', array( $this, 'filter_background_position_x' ) );
remove_theme_mod( 'background_image' );
remove_theme_mod( 'background_image_thumb' );
remove_theme_support( 'custom-background' );
set_current_screen();
wp_set_current_user( 0 );

parent::tear_down();
}

/**
* @ticket 57268
*/
public function test_admin_page_escapes_background_styles() {
set_theme_mod( 'background_image', 'https://example.org/background.jpg' );
set_theme_mod( 'background_image_thumb', 'https://example.org/background.jpg' );
set_theme_mod( 'background_size', 'cover' );
set_theme_mod( 'background_repeat', 'repeat' );
set_theme_mod( 'background_attachment', 'scroll' );

add_filter( 'theme_mod_background_position_x', array( $this, 'filter_background_position_x' ) );

$custom_background = new Custom_Background();

ob_start();
$custom_background->admin_page();
$output = ob_get_clean();

$dom = new DOMDocument();

libxml_use_internal_errors( true );
$dom->loadHTML( '<html><body>' . $output . '</body></html>' );
libxml_clear_errors();

$image = $dom->getElementById( 'custom-background-image' );

$this->assertInstanceOf( DOMElement::class, $image );
$this->assertFalse( $image->hasAttribute( 'onmouseover' ) );
}

public function filter_background_position_x() {
return 'left" onmouseover="alert(1)';
}
}
Loading