CVE-2026-84775

Really Simple Security – Simple and Performant Security (formerly Really Simple SSL) <= 9.8.0 - Unauthenticated Denial of Service

2026-09-02 00:00

Strategic Overview

Status: Patched in 9.8.1
Affected Plugin: Really Simple Security – Simple and Performant Security (formerly Really Simple SSL)
Affected Version: <= 9.8.0
CVSS: 7.5High
Weakness type: CWE-400 · Uncontrolled Resource Consumption
CVE: CVE-2026-84775

View all Really Simple Security – Simple and Performant Security (formerly Really Simple SSL) vulnerabilities

At a glance

CVE-2026-84775 is a high-severity Uncontrolled Resource Consumption vulnerability in the Really Simple Security WordPress plugin, affecting versions <= 9.8.0. It carries a CVSS score of 7.5 (reachable over the network; low attack complexity; high availability impact). Exploitation requires no authentication. The issue is fixed in version 9.8.1; sites on affected versions should update now. Disclosed September 2026, reported by Ananda Dhakal.

Vulnerability Overview

The Really Simple Security – Simple and Performant Security (formerly Really Simple SSL) plugin for WordPress is vulnerable to Denial of Service in all versions up to, and including, 9.8.0. This is due to insufficient validation of user supplied input. This makes it possible for unauthenticated attackers to make the affected site unavailable.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on availability.

CWE-400: Uncontrolled Resource Consumption

Reaching this weakness in Really Simple Security <= 9.8.0 takes no account at all. Uncontrolled resource consumption means a request can make the server do an amount of work it never bounds, because the size or repetition of the job is taken from the request rather than capped by the code.

A single caller can hold PHP workers, database connections or disk open long enough to slow the site for everyone, without needing any account or any other flaw. For Really Simple Security the fix is 9.8.1: builds <= 9.8.0 are affected, anything from 9.8.1 onward is not.

Remediation

Update to version 9.8.1, or a newer patched version

How does WordSec protect against this?

Requests carrying this pattern arrive without a session, so nothing upstream of the firewall gets a chance to reject them: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Really Simple Security 9.8.1 closes this, and updating the plugin is the step that ends it.

Firewall
Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-84775 https://www.wordfence.com/threat-intel/vulnerabilities/id/eeea5b13-54e8-4482-bdbc-6922cf96b4e1 https://nvd.nist.gov/vuln/detail/CVE-2026-84775

Related records

Other vulnerabilities in Really Simple Security – Simple and Performant Security (formerly Really Simple SSL)

CVSS Vector

7.5

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityNone
IntegrityNone
AvailabilityHigh

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