{"cve":"CVE-2026-9838","nvd":{"published":"2026-07-10T09:16:54.110","modified":"2026-07-10T15:43:30.330","status":"Deferred","description":"The ICS Calendar plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'htmltagtitle' parameter in all versions up to, and including, 12.0.9 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 vulnerability is reachable via the unauthenticated wp_ajax_nopriv_r34ics_ajax AJAX action, which accepts attacker-controlled js_args values merged over stored shortcode configuration without nonce verification, allowing the htmltagtitle key to bypass the normal shortcode allowlist check.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1},"cwes":["CWE-79"],"references":["https://plugins.trac.wordpress.org/browser/ics-calendar/tags/12.0.5.2/r34ics-ajax.php#L33","https://plugins.trac.wordpress.org/browser/ics-calendar/tags/12.0.5.2/r34ics-ajax.php#L53","https://plugins.trac.wordpress.org/browser/ics-calendar/tags/12.0.5.2/r34ics-ajax.php#L72","https://plugins.trac.wordpress.org/browser/ics-calendar/tags/12.0.5.2/templates/calendar-month.php#L40","https://plugins.trac.wordpress.org/browser/ics-calendar/tags/12.0.8.4/r34ics-ajax.php#L33"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:44:02.134301115+00:00"},"epss":{"cve":"CVE-2026-9838","score":0.00495,"percentile":0.42461,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}