CVE-2026-16495: Countdown Timer stored cross-site scripting (XSS) vulnerability
medium 6.4 plugin closed published 2026-10-14
- Affected versions
- 3.0.0 to 3.0.1
- Fixed in
- unknown
- Severity
- Medium · CVSS 6.4
- Active installs
- closed
- Type
- Stored cross-site scripting (XSS)
What an attacker needs
- Access: A logged-in account with Contributor-level access or higher.
CVSS vector (score by Wordfence): CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
What to do now
- Replace Countdown Timer. A closed plugin gets no updates through WordPress, so this hole stays open.
- Deactivate and delete it once you have a replacement (Plugins → Deactivate → Delete). Deactivating alone leaves its files on the server.
- Not sure which version you run? Check your version against every known Countdown Timer issue.
- If you ran an affected version and something looks off (new admin users, spam pages, redirects), run the free scan below.
The advisory
The Countdown Timer – Widget Countdown plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'redirect_url' Shortcode Attribute in all versions up to, and including, 3.0.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
References
- NVD CVE-2026-16495 nvd.nist.gov
- Wordfence advisory www.wordfence.com
- Plugin source plugins.trac.wordpress.org
Related
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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/widget-countdown (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.