dbcve.org
Improper Input ValidationWeakness · CWE-20

CVE-2025-12842

MEDIUM · 5.3 CVSS v3.1 Published 2025-11-19
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
62/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
The Booking Plugin for WordPress Appointments – Time Slot plugin for WordPress is vulnerable to unauthorized email sending in versions up to, and including, 1.4.7 due to missing validation on the tslot_appt_email AJAX action. This makes it possible for unauthenticated attackers to send appointment notification emails to arbitrary recipients with attacker-controlled text content in certain email fields, potentially enabling the site to be abused for phishing campaigns or spam distribution.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The Booking Plugin for WordPress Appointments – Time Slot plugin lacks proper authorization and input validation on the tslot_appt_email AJAX action, allowing unauthenticated users to trigger arbitrary email notifications. Attackers can control recipient addresses and email content, enabling phishing or spam campaigns.

MitigationUpdate to version 1.4.8 or later which adds proper validation to the AJAX action. Until patched, monitor server logs for suspicious tslot_appt_email AJAX calls.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify if the plugin is installed
    Check the WordPress plugins directory (wp-content/plugins/) for a plugin folder related to appointments, time slots, or booking. Common folder names include 'appointments-time-slot', 'tslot', or similar. Look in wp-admin/plugins.php for an 'Appointments - Time Slot' or 'Booking Plugin' entry.
    Affected if The plugin folder exists in wp-content/plugins/ and appears in the WordPress plugins list.
  2. Determine the installed plugin version
    If the plugin is installed, view the main plugin PHP file header (usually the primary plugin file in the plugin folder) and look for the 'Version:' tag in the plugin comment block. Alternatively, check the version in wp-admin/plugins.php next to the plugin name.
    Affected if The installed version is lower than 1.4.8 (for example, 1.4.7, 1.4.6, 1.3.5, etc.).
  3. Verify the AJAX endpoint is exposed without authentication
    Send a POST request to /wp-admin/admin-ajax.php with action=tslot_appt_email. Inspect whether the server responds (rather than returning a 401/403 or requiring a logged-in session). Example: curl -X POST https://yourdomain.com/wp-admin/admin-ajax.php -d 'action=tslot_appt_email'
    Affected if The AJAX call returns a response (even an error) without requiring a valid nonce or user login, indicating the endpoint is accessible to unauthenticated users.
  4. Inspect the AJAX handler code for authorization checks
    Locate the PHP file containing the tslot_appt_email AJAX handler (search for 'add_action("wp_ajax_tslot_appt_email"' or 'wp_ajax_nopriv_tslot_appt_email'). Open the file and examine the handler function for checks such as 'current_user_can()', 'is_user_logged_in()', or nonce verification using 'check_ajax_referer' or 'wp_verify_nonce'.
    Affected if The handler lacks proper authorization (no current_user_can check, no is_user_logged_in check) and does not verify a nonce before processing email parameters.
  5. Confirm input validation is missing
    In the same AJAX handler code found in the previous step, examine how the email parameters (recipient, subject, message) are handled. Look for sanitization functions like 'sanitize_email()', 'sanitize_text_field()', or validation of the recipient address before the wp_mail() call.
    Affected if The code directly uses POST/GET parameters in wp_mail() without sanitizing the recipient address, subject line, or message body.

If the Appointments - Time Slot plugin is installed with a version below 1.4.8 AND the tslot_appt_email AJAX action responds without authentication AND the handler lacks authorization checks and input validation, the environment is affected by CVE-2025-12842.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update to version 1.4.8 or later which adds proper validation to the AJAX action. Until patched, monitor server logs for suspicious tslot_appt_email AJAX calls.

Recommended fix Moderate confidence

Version greater than 1.4.7 (check WordPress plugin repository for latest stable release)

  1. Update the Booking Plugin for WordPress Appointments – Time Slot to the latest available version
  2. After updating, verify that the tslot_appt_email AJAX action is no longer accessible to unauthenticated users
  3. Review email logs to check for any unauthorized emails that may have been sent during the time the vulnerability was active
  4. Consider implementing additional email sending rate limiting or CAPTCHA on public-facing forms

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,930
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-12842 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data