CVE-2026-18496: Booking Calendar information disclosure vulnerability
medium 5.3 published 2026-10-10 · updated 2026-10-13
- Affected versions
- 11.4.3 and older
- Fixed in
- 11.5 *
- Latest version
- 12.0
- Severity
- Medium · CVSS 5.3
- Active installs
- 40,000+
- Type
- Information disclosure
* The source does not name a fixed version; this is the first wordpress.org release after the last affected version.
What an attacker needs
- Access: None. No account or login is needed.
CVSS vector (score by Wordfence): CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
What to do now
- Update Booking Calendar to 11.5 or newer (the latest is 12.0): Dashboard → Updates, or Plugins → “update now”.
- If you cannot update right away, deactivate it until you can.
- Turn on auto-updates for it: Plugins → “Enable auto-updates” on its row.
- Not sure which version you run? Check your version against every known Booking Calendar issue.
With WP-CLI:
wp plugin get booking --field=version. - If you ran an affected version and something looks off (new admin users, spam pages, redirects), run the free scan below.
The advisory
The Booking Calendar plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 11.4.3 via the wpbc_is_show_popover_in_flex_timeline() function. This makes it possible for unauthenticated attackers to extract sensitive data including names, email addresses, and phone numbers of customers who have made bookings.
References
- NVD CVE-2026-18496 nvd.nist.gov
- Wordfence advisory www.wordfence.com
- Code change (fix) plugins.trac.wordpress.org
Related
Ran an affected version? Check your site for signs of a hack
The free scan reads the public side of your site and looks for spam pages, hidden redirects, injected scripts and blacklist entries. No login, no install, about a minute.
Where this data comes from
- CVE record, score and references: NIST National Vulnerability Database (NVD), checked 2026-11-04. This product uses data from the NVD API but is not endorsed or certified by the NVD.
- Versions and install counts: wordpress.org/plugins/booking (Plugins API), fetched 2026-11-04.
- The summary, “what an attacker needs” and “what to do” sections are our plain-English reading of the record and the plugin's release history; the quoted description is the record's own text. Spot an error? Email Daniel.