Local File Inclusion in the Diza WordPress Theme (≤ 1.3.15): What Site Owners Must Do Now

Author: Hong Kong Security Expert · Date: 2025-12-24

TL;DR

A Local File Inclusion (LFI) vulnerability exists in the Diza WordPress theme affecting versions ≤ 1.3.15 and fixed in 1.3.16 (CVE-2025-68544). Although some reports labelled the issue “low priority,” real-world impact can be severe on sites where sensitive files are reachable or server/PHP configurations increase risk. If you run the Diza theme, update to 1.3.16 immediately and follow the incident steps and hardening measures below to reduce risk, detect exploitation, and recover cleanly.

This article, written from a Hong Kong security practitioner’s perspective, explains what LFI is, why it matters, how to detect exploitation, and practical steps to contain and recover.

Why you should read this (quick)

• If your site uses the Diza theme (or any theme/plugin that loads files based on user input), read this.
• Exploited LFI may expose wp-config.php, credentials, and other sensitive files.
• Immediate actions: update the theme, run a malware scan, check logs, rotate credentials.
• Longer-term: harden file permissions, restrict execution in upload directories, and monitor for anomalies.

What is Local File Inclusion (LFI)?

Local File Inclusion occurs when an application accepts user input used to build a path to a file on the server and then includes or reads that file without proper validation. In PHP-based systems like WordPress, LFI may allow an attacker to:

• Read sensitive files (for example, wp-config.php, .env files, backup files).
• Leak configuration or credential data that leads to database compromise.
• In some setups, achieve remote code execution via PHP wrappers or log poisoning if writable files containing PHP code can be included.

LFI typically uses directory traversal sequences (../) or PHP stream wrappers (e.g., php://input, php://filter) to achieve inclusion. Unlike Remote File Inclusion (RFI), LFI targets files already present on the server.

Summary of the Diza vulnerability

• Affected software: Diza WordPress theme
• Affected versions: ≤ 1.3.15
• 修复于： 1.3.16
• Vulnerability type: Local File Inclusion (LFI)
• CVE： CVE-2025-68544
• Reported disclosure date: late December 2025

The root cause is insufficient validation of a parameter used to include or require local files. The theme accepted user-controlled input that could point to filesystem locations, allowing an attacker with the reported privilege to return or execute local file contents. Real-world impact depends on server configuration, PHP settings, and the privileges of the attacker account.

Why LFI in a theme matters (realistic attack scenarios)

1. Credential exposure
   Reading wp-config.php can reveal DB credentials and salts. With DB access an attacker can exfiltrate or alter data and potentially create admin users.
2. Full site takeover
   Credential access or chained vulnerabilities (e.g., insecure uploads) can lead to remote code execution and persistent backdoors.
3. Log poisoning to achieve RCE
   If an attacker can write to a file that is later included (logs, uploads), they may inject PHP code and cause remote execution via the vulnerable include. Many hosts mitigate this by preventing PHP execution in upload areas, but configurations vary.
4. Sensitive file disclosure
   Backups, environment files, SSH keys (if misconfigured), and other private files may be disclosed.

Some reports indicate low required privileges; however, sites frequently have loose role assignments or public submission points that increase risk. Treat LFI as a serious issue.

How attackers typically find and exploit LFI (high level)

• Automated scanners and bots probe known endpoints for include parameters.
• Bots send traversal payloads (e.g., ../../../../wp-config.php) or php://filter wrappers.
• If the application returns file content or observable side-effects (errors, changed response size), the scanner reports success.
• After confirmation, attackers attempt to extract sensitive files and move laterally (DB access, backdoor installation).

Indicators often include requests with ../, php://, ，或 data:// inside parameters that the theme may use.

Immediate steps if you run Diza (or believe you’re impacted)

1. Update the theme now
   Upgrade Diza to version 1.3.16 or later — this is the most effective mitigation.
2. Limit exposure
   If you suspect active exploitation, temporarily restrict public access (maintenance mode or IP allowlist) while you investigate.
3. Scan for indicators of compromise (IoCs)
   Run a full malware scan; search the filesystem for recently modified files, suspicious admin users, and unexpected PHP files; check for new cron jobs and .htaccess changes.
4. Check logs
   Search web server logs for traversal patterns or unusual parameters; note repeated requests to the same endpoint.
5. 更换凭据
   Rotate DB credentials and WordPress admin passwords if you suspect file disclosure. Update wp-config.php with any new DB credentials.
6. Restore from clean backup if needed
   If compromise is confirmed and cleanup is uncertain, restore from a pre-compromise backup, then update and harden.
7. Post-incident audit
   Remove suspicious users, revoke unused keys/tokens, and review file permissions and logs for lateral movement.
8. Consider forensic analysis
   For sites handling sensitive data, engage a forensic team to ensure full cleanup and regulatory compliance.

Detection signatures and what to look for in logs

High-level indicators to search for in web server or WAF logs:

• Requests containing repeated ../ sequences.
• Parameters that look like file paths (e.g., file=, path=, template=, view=, page=, inc=).
• PHP stream wrappers: php://, php://filter, data://.
• Responses that suddenly include long strings, config details, or database hostnames.
• Repeated quick requests to the same endpoint (scanning behaviour).
• Suspicious user agents or non-browser UA strings.

Example safe detection rule concept (test on staging before production):

Block any request that contains:
- ../ (directory traversal) AND
- a parameter name typically used to include files (file, path, template, view, page, inc)
OR
- php:// or data:// in query string

Generic protections such as a WAF or server-level rules can translate these into defensive blocks while tuning to avoid false positives.

How managed protections help

Managed protection services and properly configured server-level defenses can reduce the attack window between disclosure and patching. Practical benefits include:

• Blocking common exploitation patterns (directory traversal, PHP wrappers) at the edge.
• Providing logging and alerting so you can detect scanning and exploitation attempts early.
• Giving time to perform safe updates and forensic analysis without immediate public exposure.

Note: these protections are a bridge — not a substitute — for applying the vendor patch and following incident response steps.

Hardening your WordPress site against LFI and similar flaws

Practical measures you can implement right away:

1. 最小权限
   Only grant users the roles they require. Limit DB user privileges to the minimum necessary.
2. Disable file editing in the admin
   Add to wp-config.php:

   define('DISALLOW_FILE_EDIT', true);

3. Harden file and directory permissions
   Files: 644 (or stricter). Directories: 755 (or stricter). wp-config.php: 600 or 640 where hosting allows.
4. Disable PHP execution in upload directories
   For Apache, place an .htaccess in wp-content/uploads:

   <FilesMatch "\.php$">
     Deny from all
   </FilesMatch>

   For Nginx, ensure PHP handling is restricted to trusted locations only.

5. Keep core, themes, plugins updated
   Routine updates reduce exposure to known vulnerabilities.
6. Use strong secrets and rotate keys
   Rotate DB passwords and regenerate WordPress salts if you suspect file disclosure.
7. Remove unused themes and plugins
   Inactive code can still be a risk if accessible.
8. Protect sensitive files
   Move backups and environment files outside the document root.
9. Periodic file integrity monitoring
   Monitor critical files for unexpected changes (core files, wp-config.php, theme files).

Safe investigation checklist (step-by-step)

1. Take a snapshot backup (files + DB) before making changes.
2. Update Diza to 1.3.16. If you cannot update immediately, apply edge/server rules that block LFI patterns for the affected theme path.
3. Run a malware scanner across filesystem and database.
4. Search for newly added PHP files in uploads or wp-content, modified theme/plugin files (last 30 days), and unknown admin users.
5. Check web server logs for suspicious requests (see detection section).
6. Rotate credentials (WP admin, DB, third-party keys).
7. Re-scan after remediation to confirm cleanup.
8. If compromise is found, restore from a clean backup, patch, and harden before restoring to production.

Practical WAF rule suggestions (conceptual)

Conceptual rules security teams can implement. Always test in staging first.

1. Block traversal in include-like parameters
   Condition: query contains ../ AND parameter name in [file, path, template, view, page, inc, include]. Action: block + log.
2. Block PHP stream wrappers
   Condition: request contains php://, data://, zip://, etc. Action: block + log.
3. Protect admin/preview endpoints
   Rate-limit or challenge clients attempting repeated requests to theme include endpoints.
4. Monitor for sudden large responses
   Alert if a known include endpoint returns a much larger-than-expected payload.

Make rules context-aware and apply path scoping (vulnerable theme paths only). Use progressive enforcement: log → challenge → block to reduce false positives.

Post-remediation monitoring and long-term steps

• Keep file integrity monitoring active.
• Schedule regular vulnerability scans and subscribe to vulnerability feeds.
• Run penetration tests for higher-risk sites (e-commerce, membership).
• Configure host alerts for anomalous process activity or PHP processes spawning shells.
• Maintain an incident playbook with communication templates, backup procedures, and recovery timelines.

Communicating with clients and stakeholders

• Notify clients about the vulnerability, impact, and remediation steps taken.
• Provide a clear timeline: detection → containment → remediation → verification.
• Supply proof of cleanup: logs showing blocked endpoints and clean scan results.
• Use pre-written templates to speed communications and reduce confusion.

Example log entries — what to watch for (sample)

192.0.2.1 - - [23/Dec/2025:12:01:05 +0000] "GET /wp-content/themes/diza/includes.php?file=../../../../wp-config.php HTTP/1.1" 200 12456 "-" "curl/7.68.0"

198.51.100.23 - - [23/Dec/2025:12:05:22 +0000] "GET /?page=php://filter/convert.base64-encode/resource=wp-config.php HTTP/1.1" 200 2048 "-" "Mozilla/5.0"

If you see these patterns, follow the investigation checklist and treat them as serious.

When to involve your host or a security specialist

• Evidence of compromise: unknown admin users, irrecoverable file changes, or backdoors.
• If you lack the technical ability to analyse logs or clean the site.
• If multiple sites on the same host show similar signs — this may indicate a server-level issue.
• For compliance-driven incidents involving payment data or customer PII.

Access controls that reduce LFI exploitation risk

• Limit write access to plugin/theme files to trusted administrators.
• Use deployments (CI/CD) to prevent direct editing on production.
• Avoid storing backups or credential files in web-accessible locations.

Final checklist — what to do now (step-by-step)

1. Update Diza to 1.3.16 or later immediately.
2. If you cannot update immediately, apply edge/server rules blocking LFI patterns for the theme path.
3. Run a full malware and file integrity scan.
4. Rotate database and admin credentials.
5. Review logs for suspicious requests and act on confirmed IoCs.
6. Harden configuration: disable file edits, disallow PHP execution in uploads, tighten permissions.
7. Consider professional cleanup and forensic assessment if you detect compromise.
8. Maintain ongoing monitoring and an incident playbook for future responses.

Closing thoughts

Vulnerabilities in themes and plugins are a recurring reality. What matters is how quickly and thoroughly you respond: timely updates, clear detection, and layered defenses reduce the chance of compromise. Treat code that reads files from disk with caution, and ensure your operational controls (permissions, execution policies, monitoring) are robust.

If you manage multiple sites, prepare standard operating procedures and communication templates now — that will save valuable time when incidents occur. Act quickly: active exploitation often happens within hours of public disclosure.