CVE-2026-12272: Lightweight Cookie Notice remote code execution vulnerability
medium 5.3 published 2026-10-16
- Affected versions
- 1.19 and older
- Fixed in
- 1.20 *
- Latest version
- 1.21
- Severity
- Medium · CVSS 5.3
- Active installs
- 5,000+
- Type
- Remote code execution
* 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 Lightweight Cookie Notice to 1.20 or newer (the latest is 1.21): 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 Lightweight Cookie Notice issue.
With WP-CLI:
wp plugin get lightweight-cookie-notice-free --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 Lightweight Cookie Notice – Cookie Banner for Cookie Consent plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 1.19 This is due to the W3TC_DYNAMIC_SECURITY constant being hardcoded to a publicly known value. This makes it possible for unauthenticated attackers to know the W3 Total Cache mfunc security key, which when W3 Total Cache is installed may allow arbitrary PHP code injection.
References
- NVD CVE-2026-12272 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/lightweight-cookie-notice-free (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.