CMP lets unauthenticated visitors disable maintenance mode
CMP before 4.1.18 omits authorization from an AJAX action and relies on a nonce that is skipped in some cases and exposed to anonymous visitors in others. Under a non-default countdown configuration, an unauthenticated attacker can disable the site's maintenance or coming-soon mode.
- Component
- CMP
- Plugin slug
cmp- Affected
- < 4.1.18
- Safe version
4.1.18- Published
- Aug 27, 2026
- Weakness
- CWE-862 — Missing Authorization
This CVE was published Aug 27, 2026 and is one of 5 known issues for this plugin.
Update, patch or deactivate.
Update to 4.1.18 or later and verify maintenance-mode, countdown, and coming-soon settings for unauthorized changes.
A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.
Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.
Technical description
The CMP WordPress plugin before 4.1.18 does not perform authorization checks on one of its AJAX actions and relies on a nonce that is skipped for certain (and exposed to anonymous visitors on others), allowing unauthenticated attackers to disable the site's maintenance/coming-soon mode under a non-default countdown configuration.
CVE / CNA vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N