Apache CVE-2026-23918 Fix Guide (CloudLinux, cPanel, AlmaLinux, Ubuntu)

Complete Guide, Impact Analysis & Fix Instructions

⚠️ CVE-2026-23918 Overview

Type: Memory Corruption (Double Free)

Severity: High (CVSS ~8.8)

Affected: Apache 2.4.66

Fixed: Apache 2.4.67+

A critical security vulnerability (CVE-2026-23918) has been identified in Apache HTTP Server, impacting systems running Apache 2.4.66.

This flaw affects the HTTP/2 module and may allow remote attackers to exploit servers without authentication.

☁️ CloudLinux Fix

The patched version ea-apache24-2.4.67 may not be immediately available in default repositories.

Use the testing repository to apply the update:

yum update ea-apache24 --enablerepo=cl-ea4-testing

🛡️ Imunify360 (Non-CloudLinux) Fix

If you are using a non-CloudLinux server with Imunify360 and ea-php-hardened, you can apply the patched Apache version using the beta repository:

yum update ea-apache24 --enablerepo=imunify360-ea-php-hardened-beta

This repository provides early access to patched packages until they are released in stable channels.

🛠️ Fix on Other Systems

RHEL-based Servers

yum clean all
yum makecache
yum -y update ea-apache*

AlmaLinux

dnf clean all
dnf makecache
dnf -y update ea-apache*

yum -y install ea-apache24-2.4.67*

Ubuntu

apt update
apt install --only-upgrade "ea-apache24*"

✅ Verify Update

httpd -v

Expected: Apache/2.4.67 or later

⚠️ Final Security Warning:
Servers running Apache 2.4.66 remain vulnerable to active threats. Immediate update is required.

Critical Apache HTTP/2 Vulnerability (CVE-2026-23918) – Full Details, Impact & Fix Guide