Local File Inclusion (LFI) in Struktur WordPress Theme (CVE-2025-69407) — What Site Owners Must Do Now

Disclosure: On 11 February 2026 a serious Local File Inclusion (LFI) vulnerability (CVE-2025-69407) was publicly disclosed in the Struktur WordPress theme affecting versions ≤ 2.5.1. The flaw allows unauthenticated attackers to include local files and display their content. This vulnerability carries a high severity (CVSS 8.1) and, at the time of disclosure, no official theme update was available that fully resolves the problem.

Reported by: Tran Nguyen Bao Khanh (VCI – VNPT Cyber Immunity). CVE reference: CVE-2025-69407.

Quick summary — what you need to know right now

• LFI exists in Struktur theme ≤ 2.5.1. Exploitable without authentication (CVE-2025-69407).
• Severity: High (CVSS 8.1). Exploitable over the public web.
• Impact: Disclosure of local files (including wp-config.php), credential theft, and possible remote code execution via log poisoning or chained exploits.
• At disclosure, no official complete fix was available — act immediately to reduce exposure.
• Immediate actions: isolate affected sites, apply HTTP-layer protections, restrict access to sensitive files, audit logs, and prepare incident response steps (rotate secrets, scan for backdoors).

Understanding Local File Inclusion (LFI) — the core risk

LFI occurs when an application builds a path to a local file from user-supplied input and then reads or includes that file without safe validation. In themes, this often involves template or include loaders that accept a parameter specifying which file to load. If that parameter is concatenated into a filesystem path without strict allowlisting or sanitisation, directory traversal and file disclosure are possible.

Typical consequences:

• Disclosure of configuration files (e.g., wp-config.php) containing DB credentials and salts.
• Exposure of server configuration, logs, or other sensitive files on disk.
• Remote code execution if an attacker can poison logs or otherwise introduce executable code into an includable file.
• Further compromise of databases, admin accounts, backups, or adjacent services on shared hosts.

When an LFI is exploitable without authentication and over the public internet, automated scanners and mass exploitation become a major threat.

How this LFI in Struktur likely works (high level)

At a high level, the Struktur theme up to version 2.5.1 exposes a file inclusion path that accepts user-controlled input and fails to restrict which files can be referenced. The theme does not enforce an allowlist of templates nor sufficiently normalise/sanitise traversal characters, allowing attackers to reference files such as:

• Relative traversal payloads (../ and encoded equivalents)
• Log files, backup files, and configuration files

In vulnerable cases an attacker requests a crafted URL and the theme reads and outputs the contents of a local file. If that file contains plaintext credentials or secrets, the attacker can escalate access or perform further attacks.

Real-world impact and attacker scenarios

Below are realistic attack chains based on this class of vulnerability:

1. Information disclosure: extract wp-config.php → obtain DB credentials → read user table and secrets.
2. Log poisoning → RCE: write PHP into a log file (via crafted requests) and include it via LFI to execute code.
3. Persistence: drop webshells or backdoors if the attacker gains write capability or through chained exploits.
4. Pivot: use leaked credentials to attack other environments (staging, backups, third-party services).
5. Operational damage: SEO spam, defacement, data leaks, and service downtime.

On shared hosting, or environments with multiple apps under the same account, the risk is amplified.

किसे चिंता करनी चाहिए

• Any WordPress site running Struktur ≤ 2.5.1 (active or present but inactive in themes directory).
• Sites on shared hosting or multi-site setups.
• Sites without HTTP-layer protections, strict file permissions, or that permit file editing from the admin UI.

Immediate detection steps — check for probes or exploitation

Early detection reduces impact. Look for:

• Access log entries with traversal patterns (%2e%2e%2f, ../) or references to wp-config.php, config.php, access.log, error.log.
• Large GET responses that reveal bits of configuration, DB credentials, or environment variables.
• Repeated strange requests for backup files, .env, .git or unusual filenames.
• New or suspicious admin accounts, unexpected file changes, or unknown outbound connections.

तत्काल शमन (चरण-दर-चरण)

If your site runs an affected Struktur version, follow these prioritized steps now:

1. Place the site into maintenance mode or take it offline temporarily if you suspect active exploitation.
2. Apply HTTP-layer protections (server rules or WAF/virtual patching) to block traversal and direct access to sensitive filenames.
3. Remove or replace the vulnerable theme:
   • If you do not actively use Struktur, delete it from Appearance → Themes → Delete.
   • If required temporarily, replace it with a known-clean theme until an official fix is available and verified.
4. Disable theme and plugin file editing in WordPress: add define('DISALLOW_FILE_EDIT', true); wp-config.php में।.
5. Restrict direct access to sensitive files:
   • Protect wp-config.php via server-level rules.
   • Disable PHP execution in /wp-content/uploads/.
6. Rotate credentials after confirming exposure: database user, API keys, and any secrets found in disclosed files.
7. Scan for malware and webshells, and inspect file integrity against known-good backups.
8. Audit logs and user accounts; remove unauthorized admin users.
9. Restore from a known-clean backup if you cannot guarantee full removal of attacker access.

Example server-level rules to mitigate LFI

Below are defensive configuration examples to blunt common LFI probes. They are intentionally generic and defensive.

Nginx (add to your server block):

# Deny direct access to wp-config.php
location ~* wp-config.php {
    deny all;
    return 404;
}

# Basic block for directory traversal patterns in query strings
if ($request_uri ~* "\.\./|\%2e\%2e|\%2e\%2f") {
    return 403;
}

# Deny requests containing common sensitive filenames
if ($request_uri ~* "(wp-config\.php|\.env|\.git|composer\.json|config\.php|\.htpasswd)") {
    return 403;
}

Apache (.htaccess in web root):

# Deny access to wp-config.php
<Files wp-config.php>
    Require all denied
</Files>

# Block obvious traversal attempts (basic)
RewriteEngine On
RewriteCond %{QUERY_STRING} (\.\./|\.\.%2f|%2e%2e) [NC]
RewriteRule .* - [F,L]

Note: These rules reduce the attack surface but are not a substitute for a proper fix in the theme code. Test config changes in a staging environment before applying to production.

What HTTP-layer protections (WAF / virtual patching) provide

When an official patch is not yet available, HTTP-layer protections can block exploit attempts before they reach the vulnerable code. Useful mitigation patterns include:

• Block requests containing directory traversal sequences in parameters.
• Block direct attempts to fetch known sensitive filenames (wp-config.php, .env, etc.).
• Allowlisting expected template identifiers where possible (positive validation).
• Rate limiting and IP reputation to reduce mass scanning/exploitation.
• Logging and alerting for blocked attempts so administrators can investigate.

If you believe your site is compromised — incident response checklist

1. Isolate: Put the site in maintenance/offline mode. If possible, take the host off public networks.
2. Preserve logs and disk snapshots for forensics.
3. क्रेडेंशियल्स को घुमाएं:
   • Create new DB credentials and update wp-config.php.
   • Rotate admin passwords and hosting/FTP credentials.
   • Regenerate WordPress salts (use the WordPress API to generate new salts).
4. Run deep malware scans and file integrity checks; compare files to clean backups or original packages.
5. Remove persistent backdoors and suspicious PHP files from uploads, themes, and plugins.
6. Restore from a verified clean backup where appropriate.
7. Re-audit all components and update to latest secure versions.
8. Monitor closely after recovery for signs of reinfection (unexpected outbound connections, new admin users, cron tasks).
9. If you handle customer data, review legal obligations and prepare notifications where required.

Hardening recommendations — reduce the surface for similar bugs

• Keep WordPress core, themes, and plugins up to date. Remove unused components from disk.
• Enforce least privilege for database accounts and OS users.
• Use strong passwords and two-factor authentication for admin accounts.
• Disable in-dashboard file editing: define('DISALLOW_FILE_EDIT', true);
• Disable PHP execution in uploads and other writable directories.
• Harden file permissions (common baseline: 644 files, 755 directories; wp-config.php can be 600 on some systems).
• Maintain regular off-site backups and verify restore procedures periodically.
• Restrict access to wp-admin by IP where feasible and rate-limit unauthenticated endpoints.
• Monitor logs, perform regular malware scans, and schedule periodic security audits.

Layered defence — recommended operational approach

From a Hong Kong security practitioner’s perspective: treat protection as layered and operational. Combine safe coding practices, timely patching, perimeter protections at the HTTP layer, proactive monitoring, and an up-to-date incident response plan. For organisations managing multiple sites, centralised controls for configuration, patching and logging materially reduce operational risk and speed recovery.

Practical detection commands and resources

Safe diagnostic commands you or your host can use:

# Search web server logs for traversal sequences
grep -E "(\.\./|\%2e\%2e|\.\.%2f|wp-config\.php|\.env|access\.log|error\.log)" /var/log/nginx/access.log /var/log/nginx/error.log

# Find PHP files in uploads
find /path/to/wordpress/wp-content/uploads -type f -iname '*.php' -print

# Find recently modified files (last 7 days)
find /path/to/wordpress -mtime -7 -type f -print

# WP-CLI: list installed themes and active theme
wp theme list
wp theme status

Generate new WordPress salts: https://api.wordpress.org/secret-key/1.1/salt/

Closing — act now, mitigate risk

This LFI in Struktur (CVE-2025-69407) is dangerous because it is unauthenticated and can expose secrets used by your site. If you run Struktur ≤ 2.5.1, treat this as urgent:

1. Apply HTTP-layer protections and block traversal patterns immediately.
2. Remove or replace the vulnerable theme where possible.
3. Audit logs for suspicious activity and follow the incident response checklist if you find evidence of exploitation.
4. Rotate credentials and harden the site as outlined above.

If you need specialist help with detection, forensics, or recovery, engage an experienced incident response provider familiar with WordPress environments. Acting promptly limits damage — attackers scan and act fast.