Remediation & cleanup if you find malicious payloads

1. Take the site to maintenance mode if practical.
2. Backup the site and database (snapshot for forensics).
3. Remove malicious content from posts and postmeta; restore safe revisions.
4. Rotate admin passwords, API keys and other secrets.
5. Invalidate sessions and require password resets for admins/editors.
6. Scan files for webshells and unauthorized changes (focus on wp-content/uploads, themes, plugins).
7. Remove unknown scheduled tasks, suspicious users and options.
8. If credentials were exfiltrated, escalate to full incident response and forensic analysis.
9. After cleanup, reinstall WordPress core, themes and plugins from trusted sources.

If you are unsure how to proceed, engage a professional security incident responder.

Developer guidance — secure shortcode patterns and fixes

If you maintain or develop the plugin, fix the shortcode handler and apply robust sanitization and escaping.

Key principles:

• Never echo user input directly.
• Validate inputs strictly (e.g., stock tickers should be alphanumeric and short).
• Sanitize input on save and escape on output.
• Use wp_kses with a strict allowlist if HTML output is required.
• Restrict who can submit HTML (capability checks) and use nonces for requests.

Illustrative safe shortcode handler (example):

function is_valid_stock_symbol( $symbol ) {
    // Accept uppercase letters, numbers, hyphen; max length 10
    return preg_match( '/^[A-Z0-9\-]{1,10}$/', $symbol );
}

function safe_stock_shortcode_handler( $atts ) {
    $atts = shortcode_atts( array(
        'symbol' => '',
        'show'   => 'price',
    ), $atts, 'stock' );

    // sanitize attributes
    $symbol = strtoupper( sanitize_text_field( $atts['symbol'] ) );
    if ( ! is_valid_stock_symbol( $symbol ) ) {
        return '';
    }

    $show = sanitize_text_field( $atts['show'] );
    $allowed_show = array( 'price', 'change', 'name' );
    if ( ! in_array( $show, $allowed_show, true ) ) {
        $show = 'price';
    }

    $symbol_escaped = esc_html( $symbol );
    $show_escaped   = esc_attr( $show );

    $output  = '';
    $output .= '' . $symbol_escaped . '';
    $output .= '';

    return $output;
}
add_shortcode( 'stock', 'safe_stock_shortcode_handler' );

Notes:

• Validate symbols; reject unexpected input.
• Use sanitize_text_field and escaping functions (esc_html, esc_attr).
• Only allow raw inner HTML for users with appropriate capabilities and sanitise with wp_kses using a strict allowlist.
• Do not store untrusted HTML or scripts in postmeta or options.

Example hardening changes at plugin level

• Add capability checks so raw HTML is only accepted by users with unfiltered_html capability.
• Escape on output: esc_html() for text nodes, esc_attr() for attributes.
• Sanitize before storing and escape again on output — defence in depth.
• Use nonces for AJAX and form endpoints and validate capabilities in REST/AJAX handlers.

WAF / virtual patching perspective (general guidance)

When a plugin fix is not yet available, virtual patching via a WAF or hosting-level rules can reduce risk. Goals for rules:

• Block attempts to save shortcodes containing script tags or inline event handlers.
• Block admin/post requests with common XSS signatures in POST bodies.
• Optionally, neutralise or strip script tags from POST payloads before WordPress saves them (use with caution).
• Prevent stored XSS payloads that reference sensitive APIs (e.g., document.cookie, XMLHttpRequest) from being saved.

Operational advice:

• Tune rules to reduce false positives; some legitimate content may contain code samples.
• Prefer challenge (captcha) in sensitive situations where false positives are likely, rather than outright block.
• Log all blocked attempts and investigate the sources of blocked traffic.

Suggested WAF regex examples (illustrative)

Test these on a staging environment before deploying to production.

• Block POST requests where a [stock shortcode contains script tags or suspicious patterns:

  (?i)\[stock[^\]]*(|on\w+\s*=|javascript:|data:text/html)

• 阻止内联事件处理程序：

  (?i)on(?:点击|鼠标悬停|加载|错误|提交)\s*=

• 阻止javascript: URI：

  (?i)javascript\s*:

根据您的环境调整规则，以避免破坏合法内容。.

长期强化检查清单

• 最小权限：仅在必要时授予贡献者/编辑角色；考虑具有更严格权限的自定义角色。.
• 编辑工作流程：要求审核并限制谁可以预览或发布包含短代码的内容。.
• 禁用不受信任角色的危险短代码。.
• 确保 未过滤的_html 不授予非受信任角色。.
• 应用严格的内容安全策略（CSP）以减少内联脚本的影响（不能替代适当的清理）。.
• 维护已安装插件/主题的清单，并删除未使用的。.
• 定期备份和测试恢复程序。.
• 基于角色的测试：模拟贡献者工作流程以识别不安全的渲染路径。.
• 监控服务器和WAF日志以发现异常和被阻止的XSS尝试。.

事件响应手册（简要）

1. 控制： 停用插件，禁用短代码，如有必要，将网站下线。.
2. 分类： 识别注入的帖子/元数据，收集日志并保存证据。.
3. 清理： 删除有效负载、未知的管理员用户和被更改的文件。.
4. 恢复： 从干净的备份恢复或从受信任的来源重新安装组件。.
5. 事后分析： 确定根本原因，修补和更新流程以避免再次发生。.
6. 通知： 如果用户数据被暴露，遵循法律和披露义务。.

如何在数据库中检测易受攻击的短代码（快速SQL）

搜索包含短代码和可能的脚本标签的帖子：

SELECT ID, post_title
FROM wp_posts
WHERE post_content LIKE '%[stock%'
AND post_content LIKE '%

SELECT post_id, meta_key, meta_value
FROM wp_postmeta
WHERE meta_value LIKE '%[stock%'
OR meta_value LIKE '%

wp db query "SELECT ID, post_title FROM wp_posts WHERE post_content LIKE '%[stock%' AND post_content LIKE '%

// Neutralize 'stock' shortcode: return safe placeholder and log the incident
if ( shortcode_exists( 'stock' ) ) {
    remove_shortcode( 'stock' );
    add_shortcode( 'stock', function( $atts ) {
        error_log( 'Blocked stock shortcode rendering in ' . (is_admin() ? 'WP-admin' : 'Front-end') );
        return '';
    } );
}