CVE-2026-4127
Speedup Optimization <= 1.5.9 - Missing Authorization to Authenticated (Subscriber+) Arbitrary Modification via 'speedup01_enabled' AJAX Action
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.
INFO
Published Date :
March 21, 2026, 4:17 a.m.
Last Modified :
March 21, 2026, 4:17 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-4127
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update the Speedup Optimization plugin.
- Verify plugin actions require proper authorization.
- Apply vendor patches when available.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-4127.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-4127 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-4127
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-4127 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-4127 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Mar. 21, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Added CWE CWE-862 Added Reference https://plugins.trac.wordpress.org/browser/speedup-optimization/tags/1.5.9/speedup-optimization.php#L172 Added Reference https://plugins.trac.wordpress.org/browser/speedup-optimization/tags/1.5.9/speedup-optimization.php#L178 Added Reference https://plugins.trac.wordpress.org/browser/speedup-optimization/trunk/speedup-optimization.php#L172 Added Reference https://plugins.trac.wordpress.org/browser/speedup-optimization/trunk/speedup-optimization.php#L178 Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/3f37c650-af0d-4474-9c1b-7f8d361b4d81?source=cve