Tên plugin	The Events Calendar
Loại lỗ hổng	Tiêm SQL không xác thực
Số CVE	CVE-2025-12197
Tính cấp bách	Cao
Ngày xuất bản CVE	2025-11-08
URL nguồn	CVE-2025-12197

Critical: The Events Calendar (v6.15.1.1–6.15.9) — Unauthenticated SQL Injection (CVE-2025-12197)

As security practitioners who build and operate a WordPress web application firewall and managed security service, we want to make sure site owners and developers fully understand the impact of the recently disclosed unauthenticated SQL injection affecting The Events Calendar plugin (versions 6.15.1.1 through 6.15.9) — tracked as CVE-2025-12197 — and exactly what to do now to protect sites and restore safety.

This advisory explains: what the vulnerability is, why it’s dangerous, how attackers may try to exploit it, how to detect compromise, immediate steps to mitigate the risk (including virtual patching with WP-Firewall), developer-level fixes to eliminate the root cause, and an incident-response checklist you can run on impacted sites.

Important facts at a glance

• Điểm yếu: Tiêm SQL không xác thực
• Các phiên bản bị ảnh hưởng: The Events Calendar plugin 6.15.1.1 — 6.15.9
• Đã sửa trong: 6.15.10
• CVE: CVE-2025-12197
• Quyền yêu cầu: none (unauthenticated)
• Đã báo cáo: 5 November 2025
• Rủi ro: High — CVSS 9.3

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Why this matters (plain language)

An unauthenticated SQL injection means an attacker can send requests from the public internet — without logging in — that influence database queries executed by the plugin. That allows attackers to read, modify, or delete data in your WordPress database. That’s extremely serious: it can lead to data theft (user emails, hashed passwords, private metadata), creation of privileged accounts, backdoors, or full site compromise. Because the vulnerability is unauthenticated and affects a widely used calendar/events plugin, the risk of rapid, mass exploitation is high.

We view this as urgent for operators — if you run The Events Calendar and cannot update immediately, make mitigation your top priority.

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What probably went wrong (technical overview — for developers)

While we’re not publishing exploit code, the typical pattern for this class of vulnerability in WordPress plugins is:

• User-supplied input (commonly a query string parameter used for searches or filters) is injected directly into SQL, or concatenated into a query string, and passed to $wpdb->get_results() or to WP_Query without proper parameterization or escaping.
• The plugin may have used the search parameter S (or another filter parameter) in a raw query or passed it into a format string that ends up being used in SQL. Because the input is not sanitized / prepared, SQL metacharacters (single quotes, comment sequences, union/select, etc.) can change the query structure.
• Unauthenticated access means attackers can craft requests with malicious input in public endpoints (public REST endpoints, admin-ajax endpoints, front-end query parameters) to trigger the vulnerable code path.

What developers should take away:

• Never construct SQL queries by concatenating user input.
• Sử dụng $wpdb->chuẩn bị() for any raw queries.
• Sử dụng WP_Query with appropriately sanitized arguments where possible.
• When building custom REST endpoints, validate and sanitize all parameters.

Example (safe patterns)

Use prepared statements with the $wpdb object:

global $wpdb;
$sql = $wpdb->prepare( "SELECT * FROM {$wpdb->prefix}events WHERE slug = %s", $slug );
$rows = $wpdb->get_results( $sql );

Sử dụng WP_Query safely:

$args = array(
  'post_type' => 'tribe_events',
  's' => sanitize_text_field( $_GET['s'] ?? '' ),
  'posts_per_page' => 10,
);
$query = new WP_Query( $args );

If your plugin or theme is passing raw $_GET / $_YÊU CẦU into SQL or WP_Query arguments without cleaning and validation, patch it.

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Immediate mitigation steps for site owners (what to do first)

If you administer a WordPress site that uses The Events Calendar plugin, follow this priority checklist immediately:

1. Cập nhật plugin
   The simplest fix: update The Events Calendar to version 6.15.10 or later as soon as possible. This removes the vulnerability at the source.
2. If you cannot update right away, apply protective controls immediately:
   – Activate WP-Firewall (or any managed WAF you trust). We provide a virtual patch that blocks the attack patterns associated with this issue until you can update.
   – Temporarily disable the plugin if updates cannot be applied and the site can function without it.
3. Restrict access to relevant endpoints
   – Block access to known front-end endpoints that handle event searches, filtering, or AJAX if not required publicly.
   – Limit access to REST and admin-ajax endpoints using an IP allowlist or rate limiting where appropriate.
4. Tighten web server rules
   – Add web server rules to block requests with suspicious payloads (see WAF tuning below).
5. Monitor logs and scan
   – Enable detailed logging and scan for Indicators of Compromise (IoCs) immediately (listed below).
6. Change critical credentials after investigation
   – If you discover signs of compromise (see IoCs below), rotate database credentials, all administrator passwords, and WordPress salts/keys.

If you’re using our WP-Firewall service, we will:

• Push a virtual patch rule that blocks the attack attempts matching the known injection patterns.
• Monitor and report attempts targeting your site.
• Keep the rule active until you update to 6.15.10.

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Detecting exploitation — what to look for (Indicators of Compromise)

Attackers exploiting an SQL injection will often leave traces. Check these locations and signatures:

• Unusual HTTP requests in web server logs:
  • Requests with s= or other query params containing SQL keywords (LIÊN ĐOÀN, LỰA CHỌN, SƠ ĐỒ THÔNG TIN, GROUP_CONCAT, BENCHMARK, SLEEP, --, #, /*), hex-encoded payloads, or long encoded strings.
  • High frequency of requests to a particular endpoint (automated scanning).
• Người dùng quản trị mới hoặc đã sửa đổi:
  • Kiểm tra wp_người dùng for unexpected admin-level accounts.
  • Kiểm tra wp_usermeta for changed capabilities.
• Modified core, theme, or plugin files:
  • Use file integrity tools to detect unexpected file edits. Look for giải mã base64(), đánh giá(), obscure includes, or new PHP files in wp-content/tải lên.
• Strange scheduled tasks (wp-cron):
  • wp_tùy_chọn entry cron containing unknown scheduled tasks.
• Unexpected posts, pages, or options:
  • Kiểm tra wp_posts for posts with zero-length content or injected payloads.
  • Kiểm tra wp_tùy_chọn for modified values (home, siteurl, active_plugins).
• Exported database anomalies:
  • Unexpected rows in options, posts, comments, or usermeta tables. Large strings that look like dumped data.

Run these queries to hunt for common signs (example read-only queries):

-- Find recent user registrations
SELECT ID, user_login, user_email, user_registered FROM wp_users ORDER BY user_registered DESC LIMIT 20;

-- Inspect options for serialized entries with "cron" or unexpected data
SELECT option_name, option_value FROM wp_options WHERE option_name LIKE '%cron%' OR option_value LIKE '%eval(%' LIMIT 20;

-- Search posts for suspicious content
SELECT ID, post_title FROM wp_posts WHERE post_content LIKE '%base64_%' OR post_content LIKE '%eval(%' LIMIT 50;

Note: run queries on a read-only copy when possible.

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Incident response: what to do if you find evidence of compromise

If you find IoCs, assume compromise and act methodically:

1. Take the site into maintenance mode / remove public access (if possible).
2. Preserve forensic data: copy logs, export the database, and take a file-system snapshot.
3. Change all passwords and rotate database credentials (but only after preserving data).
4. Revert to a clean backup known to be from before the compromise — only if you are sure it’s clean.
5. If no clean backup exists, rebuild from scratch:
   • Export content (posts, media) but scan/clean before re-importing.
   • Re-install WordPress core, themes, and plugins from official sources.
6. Scan the restored site with multiple tools (malware scanner, file integrity).
7. Harden configuration (see hardening checklist below).
8. Monitor for re-infection and closely inspect logs for repeated exploitation attempts.

If you are not confident performing a full incident response, engage a professional incident response provider. Quick and correct remediation prevents reinfection and lateral persistence.

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Virtual patching and WAF guidance (practical — how mitigation helps now)

Virtual patching is not a replacement for updating, but it is an essential stopgap when patches cannot be installed immediately. WP-Firewall implements virtual patches as tuned WAF rules. Below are practical examples of what effective rules should do for this vulnerability class:

1. Block SQL injection patterns in query parameters
   • Focus on public parameters used by The Events Calendar (e.g., search query param S or similar). Instead of blacklisting everything containing “select”, use context-aware patterns like:
     • Deny requests where parameter S contains SQL keywords and special characters (e.g., union+select, information_schema, group_concat, benchmark().
     • Deny requests containing SQL comment syntax combined with other keywords (e.g., --, #, /* following a string).
2. Use positive security for endpoints
   • For known endpoints that accept only alphanumeric or short strings, apply a whitelist: allow only the expected character set and length.
3. Rate-limiting and request throttling
   • Apply rate limits to suspicious requests to prevent automated exploitation.
4. Block common tamper patterns
   • Deny base64-encoded payloads in query strings and requests larger than typical search queries.
5. Monitor anomaly scores
   • Assign anomaly scores and block high-score requests by default.

Example of a context-aware rule (conceptual, not an exact WAF syntax):
If request path matches /events/* hoặc /wp-admin/admin-ajax.php AND query param S matches regex (case-insensitive): \b(union|select|information_schema|group_concat|benchmark|sleep)\b|(--|#|/\*) THEN block and alert.

Quan trọng: overly broad SQL keyword blocking will break legitimate searches that may legitimately contain words like “select” (e.g., an academic event named “Select”), so rules must be contextual and include length/charset checks.

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How we tune our WP-Firewall protections for this issue

As a managed WAF vendor operating in WordPress environments, we apply the following layered approach:

• Rapid virtual patch deployment: push targeted rules that intercept the attack vectors used in public exploits without breaking normal searches or plugin behavior.
• Behavioral detection: look for patterns (e.g., many different IPs hitting the same vulnerable endpoint within short time) and block suspicious IPs.
• Retrospective scanning: once a site is protected, we scan historical logs and traffic for successful injections.
• Alerting and guidance: notify site owners of attempted and blocked attacks and provide remediation steps.
• Automatic updates: when plugin updates are available, guide or automate the update (depending on the customer’s setup).

If you run WP-Firewall, these protections can be enabled instantly and remain until you have applied the official plugin update.

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Long-term fixes for plugin authors (developer checklist)

Plugin authors and maintainers should take the disclosure as a reminder of safe coding practices:

• Nguyên tắc đặc quyền tối thiểu:
  • Ensure public endpoints do not expose admin-level functionality.
• Khử trùng và xác thực mọi dữ liệu đầu vào:
  • Sử dụng filter_input(), vệ sinh trường văn bản(), wp_parse_args(), and explicit type checks.
• Use parameterized queries:
  • $wpdb->chuẩn bị() for any custom SQL.
• Prefer WordPress API functions:
  • Sử dụng WP_Query, get_posts(), and other APIs that abstract away SQL when possible.
• Implement unit tests and fuzz testing:
  • Add tests that pass a variety of benign and malicious inputs to public endpoints.
• Add logging for suspicious inputs:
  • Log requests that contain special chars + SQL-like patterns for review.
• Perform regular security reviews and dependency checks.

Adopting these controls reduces the risk of future injection-style vulnerabilities.

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Operational hardening checklist (for site owners)

Beyond immediate mitigation and patching, harden your WordPress environment:

• Keep WordPress core, plugins, and themes up to date.
• Use strong, unique admin passwords and enforce 2FA for admins.
• Limit admin user counts and audit user roles frequently.
• Use least-permission SFTP/FTP accounts and avoid exposing credentials.
• Maintain offline backups with versioning; store backups off-site and test restores.
• Enable file integrity monitoring to detect unauthorized changes.
• Run regular malware scans and database integrity checks.
• Keep database and web server logs centralized and watched for anomalies (SIEM).
• Use secured database users — avoid using root or high-privilege DB accounts.
• Rotate salts and security keys if you suspect credential theft.

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Testing and verification after remediation

After applying the plugin update and/or virtual patch, verify:

• Confirm plugin is updated to v6.15.10+.
• Re-run your WAF/virtual patch logs to ensure no blocked attempts are succeeding.
• Validate that public site functionality is intact (search, filters, event listings).
• Rescan the site for malware and indicators of earlier compromise.
• Confirm all admin users are legitimate.
• Check file modification times for unexpected recent edits.

If you used a backup to restore, check that the restored site behaves as expected and monitor for re-infection.

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What attacks could look like (high-level — no exploit details)

Exploitation might look like:

• An attacker sends a specially crafted GET or POST request to a publicly available events endpoint, passing a maliciously constructed S parameter (or other filter parameter). If the plugin includes that parameter unsafely into SQL, the attacker may cause the database to return unexpected data, or write data (if queries include INSERT/UPDATE), or create admin users via injection into options or usermeta tables.
• Automation: attackers often scan large numbers of sites and then automatically inject payloads for successful targets. Because the vulnerability is unauthenticated, even low-skill attackers can attempt exploitation at scale.

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Câu hỏi thường gặp (FAQ)

Hỏi: I updated — am I safe?
MỘT: If you updated The Events Calendar to 6.15.10 or later, you have the vendor fix and should be safe from this specific vulnerability. Still follow the detection checklist to ensure you were not compromised prior to update.

Hỏi: I can’t update because of customizations — what should I do?
MỘT: If update is not feasible immediately, enable a managed WAF with virtual patching to block exploit attempts, restrict access to vulnerable endpoints, and schedule a plan to update or patch the customizations so you can upgrade.

Hỏi: Is a virtual patch sufficient forever?
MỘT: No. Virtual patching is a bridge that prevents exploitation while you plan and implement the official fix. Always update plugins to the official fixed versions as soon as practical.

Hỏi: I found suspicious activity — should I restore a backup?
MỘT: If you have a trusted, clean backup from before the suspected compromise, restoring is often the fastest clean-up. Preserve forensic data before restoring and rotate all credentials after restoration.

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Final recommendations (clear, practical)

1. Update The Events Calendar plugin to v6.15.10 immediately.
2. If you cannot update immediately, enable WP-Firewall virtual patching / managed WAF to block known exploitation attempts.
3. Audit logs and scan for indicators of compromise. If you find anything suspicious, treat it as a potential compromise and follow the incident response checklist.
4. Harden your site to reduce the blast radius of any future vulnerabilities — restrict access, use 2FA, rotate keys/credentials after incidents, and maintain good backups.
5. For developers: adopt parameterized queries, sanitize every input, and prefer core APIs rather than raw SQL.

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If you want help implementing the mitigations above, hardening your environment, or running a forensic scan, our WP-Firewall team is available to assist. We can deploy virtual patching across sites quickly and provide monitoring and remediation guidance tailored to your environment. Stay safe and prioritize this update — unauthenticated SQL injection can be devastating, but with prompt action you can stop attacks and recover safely.