Critical Broken Access Control in “Integrate Google Drive” WordPress Plugin (≤ 1.3.8): What Site Owners Must Do Right Now

日期： 3 Feb 2026
CVE： CVE-2024-2086
嚴重性： Critical (CVSS: 10.0)
受影響版本： Integrate Google Drive ≤ 1.3.8
修復於： 1.3.9

TL;DR — A broken access control vulnerability in Integrate Google Drive (≤ 1.3.8) allows unauthenticated attackers to read and modify plugin settings and export configuration. Because the plugin stores Google API credentials and integration tokens, successful exploitation can expose OAuth tokens, enable unauthorized Google Drive access, and lead to site compromise. Update to 1.3.9 immediately. If you cannot update right away, use the mitigation and recovery guidance below.

Who we are and why you should read this

We are Hong Kong–based security practitioners with hands‑on experience responding to WordPress incidents and securing web applications in APAC environments. This advisory explains the vulnerability, the risk it poses for real sites, how attackers may abuse it conceptually, and practical, non‑vendor recommendations for containment and recovery. The guidance assumes you are familiar with WordPress administration and basic server operations.

What exactly is “Broken Access Control” in this context?

Broken access control here means the plugin exposes administrative functionality without enforcing authentication and capability checks. Vulnerable endpoints allow exporting configuration (which may include OAuth client IDs/secrets and refresh tokens) or modifying plugin options without verifying the request origin or user permissions.

後果包括：

• Exporting sensitive configuration (OAuth client IDs/secrets, refresh tokens) that can be used to access Google Drive resources.
• Changing plugin configuration to enable malicious or unexpected behavior (e.g., altering allowed file types, enabling remote callbacks).
• Installing persistent backdoors, malicious cron jobs, or adding unauthorized users.
• Pivoting from plugin-level access to full site compromise or exfiltration of data stored in linked Google Drive accounts.

Because the endpoints are accessible without authentication, automated scanners and opportunistic attackers can target affected sites en masse.

How an attacker could abuse this vulnerability (conceptual)

No exploit code is published here. High‑level abuse flow:

1. The plugin exposes an unauthenticated endpoint (via admin-ajax.php or a REST route) that accepts requests to export settings or write options.
2. The endpoint fails to check: user authentication, capability (e.g., manage_options), valid nonces, or appropriate REST permission callbacks.
3. An attacker issues requests to the endpoint to retrieve configuration or to modify settings.
4. If configuration includes OAuth refresh tokens or client secrets, the attacker can use them to access the linked Google Drive, enumerating or exfiltrating files.
5. Subsequent actions may include planting web shells, creating admin users, or using the site for phishing/malware distribution.

Because no authentication is required, the risk is elevated and wide‑ranging.

立即行動（前 24 小時）

If your site uses Integrate Google Drive and you cannot confirm a safe version is installed, act now. Prioritise actions by feasibility.

1. Update the plugin to version 1.3.9 or later. This is the definitive fix—apply it immediately where possible.
2. 如果您無法立即更新：
   • Deactivate the plugin from WordPress admin » Plugins.
   • If admin access is not available, rename the plugin folder via SFTP/SSH:

     mv wp-content/plugins/integrate-google-drive wp-content/plugins/integrate-google-drive.disabled

3. Revoke and rotate Google OAuth tokens and credentials used by the plugin:
   • Sign in to the Google account / Google Cloud Console associated with the integration.
   • Revoke app access and rotate client secrets or credentials where possible.
4. Reset WordPress administrative passwords and any associated service credentials that may have been exposed.
5. Place temporary protections to block unauthenticated access to plugin endpoints:
   • Deploy WAF or server rules that block requests to admin-ajax.php / REST endpoints for unauthenticated clients targeting the plugin’s actions (examples below).
6. Run a malware scan and integrity check to find suspicious files, cron jobs, or new users:
   • Scan for recent file changes, web shells and unexpected PHP files in uploads or plugin directories.

How to check if your site was targeted or compromised

Perform a forensic review focusing on common indicators of exploitation:

1. 檢查網頁伺服器和訪問日誌:
   • Look for POST/GET requests to /wp-admin/admin-ajax.php with unusual action parameters or requests to plugin-created REST routes.
   • Identify repeated requests from the same IPs or suspicious user agents.
2. Inspect plugin options and settings in the database:

   wp db query "SELECT option_name, option_value FROM wp_options WHERE option_value LIKE '%google%';" --skip-column-names

   Check for OAuth tokens, client IDs/secrets, redirect URIs or anomalous values.

3. Look for new administrative users:

   wp 使用者列表 --role=administrator

   Investigate and remove any unfamiliar admin accounts.

4. Search for unexpected scheduled tasks:

   wp cron 事件列表

   Look for plugin-related hooks or unknown recurring jobs.

5. Check uploads and plugin directories for suspicious files:

   find wp-content/uploads -type f -name "*.php" -mtime -14

6. Inspect linked Google Drive activity:
   • Review account activity and Workspace audit logs (if available) for unusual OAuth usage or file operations.
   • Check for files shared externally that you did not authorise.
7. Check outbound connections from the server:

   netstat -plant | grep ESTABLISHED
   lsof -i

   Identify suspicious external connections originating from the host.

Preserve logs and evidence. If you find active compromise, consider taking the site offline (maintenance mode) and engage incident response resources as needed.

Containment and recovery checklist (detailed)

1. 隔離和控制:
   • Enable maintenance mode to limit public access.
   • Block known malicious IPs and user agents at the host firewall.
   • Revoke plugin-specific tokens and integrations tied to the plugin.
2. 修補和加固:
   • Update Integrate Google Drive to 1.3.9 or later.
   • Update WordPress core, themes, and other plugins.
   • Apply OS and host patches where relevant.
3. 清理和恢復:
   • Restore from a clean backup taken before the suspected compromise, if available.
   • Ensure backups are free from malicious code; rotate passwords and tokens after restore.
4. Credential reset and token rotation:
   • Rotate WordPress admin passwords, database credentials (if suspected), and any third‑party API keys.
   • Revoke and reissue OAuth refresh tokens and client secrets used by the plugin.
5. 移除持久性:
   • Remove web shells, rogue scripts, unauthorized admin users, and malicious cron jobs.
   • Audit filesystem and remove any suspicious files.
6. 驗證和監控:
   • Re-scan with a malware scanner and monitor logs for at least 30 days.
   • Monitor Google Drive activity for continued unauthorized access.
7. 事件後審查:
   • Perform root cause analysis and implement lessons learned (change control, plugin inventory, automated patching).

WordPress and Google Drive specific steps

• Revoke app access from the Google Account:
  • Google Account > Security > Third‑party apps with account access — remove entries for the site/app.
• In Google Cloud Console:
  • Rotate OAuth client secrets tied to the integration.
  • Review OAuth consent screen and app verification status.
• If a service account JSON key was used, rotate keys and remove old JSON files from the site.
• If files on Google Drive were accessed, collect Workspace or account audit logs for the timeframe of suspected activity to determine scope of exposure.

Best developer practices (how plugin authors should have prevented this)

Plugin authors must implement strict controls for any privileged actions. Mandatory measures include:

• 能力檢查： Use current_user_can() before performing admin operations.
• 隨機數驗證： Use check_admin_referer() / wp_verify_nonce() for admin actions and form submissions.
• REST API 權限回調： Register routes with permission_callback enforcing authentication and capability checks.
• Input/output handling: Sanitize inputs (sanitize_text_field(), wp_kses_post()) and escape outputs (esc_html(), esc_attr()).
• 最小特權： Minimise token scopes and avoid long‑lived tokens where possible; provide clear rotation guidance.
• Restrict exports: Require authentication and logging for any configuration export endpoints.
• Logging and rate limiting: Log admin changes and consider rate limits or alerts on repeated export attempts.
• Secure storage: Avoid storing plaintext secrets in files; use properly escaped, access-controlled storage.

Practical WAF / server rule examples you can apply now

If you cannot update immediately, deploy temporary rules to block unauthenticated requests to the plugin’s vulnerable endpoints. Test rules on staging before applying to production.

General pattern

Block requests to admin-ajax.php or REST routes where the request targets the plugin action and no authentication cookie is present.

Nginx（概念性）

location = /wp-admin/admin-ajax.php {
  if ($arg_action ~* "(igd_export|igd_update_settings|igd_save)") {
    if ($http_cookie !~* "wordpress_logged_in_") {
      return 403;
    }
  }
}

ModSecurity（概念性）

SecRule REQUEST_URI "@contains /wp-admin/admin-ajax.php" "chain,deny,status:403,log,msg:'Block unauthenticated Integrate Google Drive ajax export'"
SecRule ARGS:action "@rx ^(igd_export|igd_update_settings|igd_save)$" "chain"
SecRule &REQUEST_HEADERS:Cookie "@eq 0" "t:none"

Also consider rate limiting and blocking suspicious user agents targeting admin-ajax.php. These mitigations are temporary—apply only until the plugin is updated.

Hardening recommendations (short and long term)

• Maintain an inventory of plugins and only install from trusted sources.
• Enable tested auto‑updates for actively maintained plugins.
• Use a staging environment to test updates before production rollout.
• Limit administrative access by IP where feasible (restrict wp-admin to known IP ranges).
• Enforce two‑factor authentication for all administrator accounts.
• Centralise log monitoring and consider host‑based intrusion detection.
• Use strong, unique passwords and consider secrets management for API credentials.
• Keep regular backups off‑site and test restores.

Example commands and helpers (safe, non‑destructive)

Run these commands from the server shell or via WP‑CLI (replace values as needed). Make a backup before making any destructive changes.

• 列出插件版本：

  wp plugin get integrate-google-drive --field=version

• Deactivate plugin quickly:

  wp plugin deactivate integrate-google-drive --skip-plugins --skip-themes

• Rename plugin directory (SFTP/SSH):

  mv wp-content/plugins/integrate-google-drive wp-content/plugins/integrate-google-drive.disabled

• Search database for likely plugin options containing sensitive tokens:

  wp db query "SELECT option_name FROM wp_options WHERE option_value LIKE '%google%' LIMIT 50;" --skip-column-names

• 列出管理員用戶：

  wp 使用者列表 --role=administrator

• 列出排定的任務：

  wp cron 事件列表

When to call in professional help

Engage professional incident response if you encounter:

• Large‑scale data exfiltration from Google Drive linked to the site.
• Signs of arbitrary code execution, web shells, or persistent backdoors.
• Unknown admin users or unexplained database modifications.
• Evidence the site is part of a broader compromise across your infrastructure.

Incident responders can preserve evidence, safely remediate, and assist with compliance reporting.

Why this vulnerability matters beyond a single plugin

Broken access control is a common cause of WordPress compromises. Plugins integrating external services are higher risk because they hold credentials granting access to external resources. Compromise of those credentials allows attackers to pivot outside the WordPress environment—exfiltrating documents or tampering with backups and business records.

Final checklist for administrators

• Update the plugin to 1.3.9 now.
• If you cannot update, deactivate the plugin and apply temporary WAF/server rules to block unauthenticated plugin endpoints.
• Revoke and rotate Google OAuth tokens/credentials used by the plugin.
• Run a full malware and integrity scan; investigate logs and user accounts.
• Rotate WordPress and hosting credentials if exposure is suspected.
• Enable two‑factor authentication and restrict admin access where feasible.
• Keep backups and monitor activity for at least 30 days after remediation.

參考文獻： CVE-2024-2086 (MITRE)

Authored by: Hong Kong Security Expert