HomeWordPress vulnerabilitiesICS Calendar
ICS Calendar vulnerabilities
ICS Calendar has 1 known vulnerability in this database. The most recent published record is dated 10 Jul 2026.
- Known vulnerabilities
- 1
- Active installs
- 10,000+
- Latest version
- 12.1.4.1
- Last updated
- 21 Sep 2026
- Most recent
- 10 Jul 2026
Find it in your WordPress dashboard under Plugins. Severity is based on the CVSS score published with the CVE where one is available.
| Vulnerability | Severity | Affected | Fix | Published |
|---|---|---|---|---|
| Cross-site scripting (XSS) CVE-2026-9838 | Medium 6.1 | Up to 12.0.9 | Fixed in a later version (latest 12.1.4.1) | 10 Jul 2026 |
Read the published descriptions
- CVE-2026-9838, 10 Jul 2026
- 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. CVE record
What to do if you run ICS Calendar
If you run ICS Calendar, open WordPress and check the installed version in Plugins. Compare it with the affected versions in the vulnerability record. If a fixed version is available, take a current backup and update to that version or the latest supported release.
If no fixed version exists, consider disabling and removing the plugin or replacing it with a maintained alternative. After dealing with the affected software, check administrator users, unexpected file changes, redirects, unfamiliar pages and security logs for signs that the site may already have been altered.
Email me about new ICS Calendar vulnerabilities
Free. We email you when a new vulnerability is published for ICS Calendar, usually within minutes. Confirm by email; unsubscribe any time.
Focus on your business. We’ll take care of your website.
From everyday updates to ongoing care, we keep your website working.