WordPress

WordPress TutorialRemove Version from WordPress and StylesheetsRun WordPress local with XAMPPSecurity in WordPress - EscapingSecurity in WordPress - SanitizationThe Loop (main WordPress loop)Update WordPress ManuallyWordPress Actions and FiltersWordPress add action()WordPress add editor style()WordPress add menu page()WordPress Add ShortcodeWordPress add submenu page()WordPress add theme support()WordPress Add/remove contact info for users with user contactmethods filter hookWordPress Admin Dashboard WidgetsWordPress AJAXWordPress Alternating main loop (pre get posts filter)WordPress Child Theme BasicsWordPress Create a Post ProgrammaticallyWordPress Create Template for Custom Post TypeWordPress Creating a custom templateWordPress Custom exerpts with excerpt length and excerpt moreWordPress Custom Post TypesWordPress Customizer Basics (Add Panel, Section, Setting, Control)WordPress Customizer Hello WorldWordPress DebuggingWordPress Enqueuing scriptsWordPress Enqueuing StylesWordPress Function : wp trim words()WordPress Function: add action()WordPress get bloginfo()WordPress get home path()WordPress get option()WordPress get permalink()WordPress get template part()WordPress get the category()WordPress get the title()WordPress home url()WordPress How Can I integrate Markdown editor with Advance Custom Fields repeater Add-on.WordPress initWordPress Installation and ConfigurationWordPress Making network requests with HTTP APIWordPress Meta BoxWordPress Options APIWordPress Plugin creationWordPress Plugin developmentWordPress Post FormatsWordPress Querying postsWordPress Remove Auto Line Breaks from Content and ExcerptWordPress REST APIWordPress Secure your installationWordPress ShortcodeWordPress Shortcode with attributeWordPress ShortcodesWordPress SidebarsWordPress Site MigrationWordPress TaxonomiesWordPress Template hierarchyWordPress template includeWordPress the $wpdb ObjectWordPress the Admin Bar (aka The Toolbar)WordPress the title()WordPress theme and child-theme developmentWordPress ThemesWordPress wp get current user()WordPress WP Query() LoopWordPress WP-CLIWordPress WP-Cron



Security in WordPress - Escaping

From WikiOD

Syntax[edit | edit source]

  • esc_html( string $text )
  • esc_url( string $url, array $protocols, string $_context )
  • esc_js( string $text )
  • wp_json_encode( mixed $data, int $options, int $depth = 512 )
  • esc_attr( string $text )
  • esc_textarea( string $text )

Remarks[edit | edit source]

Security should be always in mind when developing. Without security an app is open to various attacks such as SQL Injections, XSS, CSRF, RFI etc that can lead to serious problems.

Untrusted data comes from many sources (users, third party sites, your own database!, ...) and all of it needs to be validated both on input and output. (Source: WordPress Codex)

The data should be validated, sanitized or escaped depending the use and the purpose.

To validate is to ensure the data you've requested of the user matches what they've submitted. (Source: WordPress Codex)

Sanitization is a bit more liberal of an approach to accepting user data. We can fall back to using these methods when there's a range of acceptable input. (Source: WordPress Codex)

To escape is to take the data you may already have and help secure it prior to rendering it for the end user. (Source: WordPress Codex)

escape data in HTML code[edit | edit source]

esc_html should be used anytime we're outputting data inside HTML code.

<h4><?php echo esc_html( $title ); ?></h4>

escape a url[edit | edit source]

<a href="<?php echo esc_url( home_url( '/' ) ); ?>">Home</a>

<img src="<?php echo esc_url( $user_picture_url ); ?>" />

escape data in js code[edit | edit source]

esc_js() is intended to be used for inline JS, inside a tag attribute.

For data inside a <script> tag use wp_json_encode().

<input type="text" onfocus="if( this.value == '<?php echo esc_js( $fields['input_text'] ); ?>' ) { this.value = ''; }" name="name">

wp_json_encode() encodes a variable into JSON, with some sanity checks.

Note that wp_json_encode() includes the string-delimiting quotes automatically.

<?php
$book = array(
    "title" => "JavaScript: The Definitive Guide",
    "author" => "Stack Overflow",
);
?>
<script type="text/javascript">
var book = <?php echo wp_json_encode($book) ?>;
/* var book = {
    "title": "Security in WordPress",
    "author" => "Stack Overflow",
}; */
</script>

or

<script type="text/javascript">
    var title = <?php echo wp_json_encode( $title ); ?>;
    var content = <?php echo wp_json_encode( $content ); ?>;
    var comment_count = <?php echo wp_json_encode( $comment_count ); ?>;
</script>

escape attributes[edit | edit source]

<input type="text" value="<?php echo esc_attr($_POST['username']); ?>" />

escape data in textarea[edit | edit source]

<textarea><?php echo esc_textarea( $text ); ?></textarea>

Credit:Stack_Overflow_Documentation