WordPress security changelog
MEDIUM CVE-2026-2518 Deferred

FastX: A security weakness

FastX is affected by a security weakness. Exploitation requires at least subscriber-level access. The resulting impact depends on how the affected component exposes the vulnerable operation. The published affected range is <= 1.0.2.

CVE / CNA score 4.3 CVSS 3.1 · security@wordfence.com
NVD score Pending NVD has not published its own CVSS assessment.
Component
FastX
Plugin slug
fastx
Affected
<= 1.0.2
Safe version
> 1.0.2
Published
May 22, 2026
Weakness
CWE-862 — Missing Authorization

This CVE was published May 22, 2026 and is one of 1 known issue for this theme.

Update, patch or deactivate.

Update FastX to a release after 1.0.2, or disable and remove it until a fixed version is available.

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 FastX theme for WordPress is vulnerable to unauthorized limited plugin installation and activation due to missing capability checks on the 'ultp_install_callback' and 'ultp_activate_callback' functions in all versions up to, and including, 1.0.2. This makes it possible for authenticated attackers, with Subscriber-level access and above, to install and activate the PostX plugin.

CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Primary and upstream sources