CVE-2026-6443 (CVSS 9.8)

Description

All plugins by Essentialplugin for WordPress are vulnerable to an injected backdoor in various versions. This is due to the plugin being sold to a malicious threat actor that embedded a backdoor in all of the plugin's they acquired. This makes it possible for the threat actor to maintain a persistent backdoor and inject spam into the affected sites.

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CVSS v3.1 Score

9.8

CRITICAL

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

EPSS — Exploit Prediction

0.0006

Probability of exploitation

0.18%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-506 CWE-506

References

Other References

https://anchor.host/someone-bought-30-wordpress-plugins-and-planted-a-backdoor-in-all-of-them/ https://www.wordfence.com/threat-intel/vulnerabilities/id/2597724a-9a39-4e46-b153-f42366f833ba?source=cve

Frequently Asked Questions

What is CVE-2026-6443? +

All plugins by Essentialplugin for WordPress are vulnerable to an injected backdoor in various versions. This is due to the plugin being sold to a malicious threat actor that embedded a backdoor in all of the plugin's they acquired. This makes it possible for the threat actor to maintain a persistent backdoor and inject spam into the affected sites. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2026-6443? +

CVE-2026-6443 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0006, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-6443? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2026-6443