CVE-2026-4127 — MEDIUM (4.3)

Vulnerability Description

The Speedup Optimization plugin for WordPress is vulnerable to Missing Authorization in all versions up to and including 1.5.9. The `speedup01_ajax_enabled()` function, which handles the `wp_ajax_speedup01_enabled` AJAX action, does not perform any capability check via `current_user_can()` and also lacks nonce verification. This is in contrast to other AJAX handlers in the same plugin (e.g., `speedup01_ajax_install_iox` and `speedup01_ajax_delete_cache_file`) which properly check for `install_plugins` and `manage_options` capabilities respectively. This makes it possible for authenticated attackers, with Subscriber-level access and above, to enable or disable the site's optimization module by sending a POST request to admin-ajax.

CVSS Score

4.3

MEDIUM

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

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

LOW

Availability

NONE

Related Weaknesses (CWE)

CWE-862

References

FAQ

What is CVE-2026-4127?

CVE-2026-4127 is a vulnerability with a CVSS score of 4.3 (MEDIUM). The Speedup Optimization plugin for WordPress is vulnerable to Missing Authorization in all versions up to and including 1.5.9. The `speedup01_ajax_enabled()` function, which handles the `wp_ajax_spee...

How severe is CVE-2026-4127?

CVE-2026-4127 has been rated MEDIUM with a CVSS base score of 4.3/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-4127?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.