XSS in Netweblogic Events Manager – Calendar, Bookings, Tickets, And More!

CVE-2026-17089

The Events Manager – Calendar, Bookings, Tickets, and more! plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'header_format' parameter in all versions up to, and including, 7.4.0.1 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. The shortcode entry point sanitizes 'header_format' via wp_kses(), but the unauthenticated 'search_events_grouped' AJAX action bypasses this sanitization entirely, leaving the parameter unsanitized before it is echoed into the HTML body in output_grouped().

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.004 (33.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 33.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-17089: held from 0.003 to 0.004.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-17089?
CVE-2026-17089 is a medium-severity vulnerability in Netweblogic Events Manager – Calendar, Bookings, Tickets, And More!, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-08-25.
How severe is CVE-2026-17089?
Medium severity. CVSS v3 base score is 6.1 out of 10.
Is CVE-2026-17089 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.