8.8
HIGH CVSS 3.1
CVE-2026-23918
Apache HTTP Server: http2: double free and possible RCE on early reset
Description

Double Free and possible RCE vulnerability in Apache HTTP Server with the HTTP/2 protocol. This issue affects Apache HTTP Server: 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue.

INFO

Published Date :

May 4, 2026, 3:16 p.m.

Last Modified :

May 4, 2026, 8:24 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-23918 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.

ID Vendor Product Action
1 Apache http_server
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 134c704f-9b21-4f2e-91b3-4a467353bcc0
Solution
Upgrade Apache HTTP Server to version 2.4.67 to fix memory corruption and potential RCE.
  • Upgrade Apache HTTP Server to 2.4.67.
  • Apply vendor patches for HTTP/2.
Public PoC/Exploit Available at Github

CVE-2026-23918 has a 13 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

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-2026-23918.

URL Resource
https://httpd.apache.org/security/vulnerabilities_24.html Vendor Advisory
http://www.openwall.com/lists/oss-security/2026/05/04/19 Mailing List Third Party Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-23918 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-2026-23918 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).

CVE-2026 PoC Collection - 128 PoCs covering 84 CVEs

Python Dockerfile Shell Java C Makefile Objective-C Rust C++ Go

Updated: 3 days, 8 hours ago
0 stars 0 fork 0 watcher
Born at : May 21, 2026, 3:15 p.m. This repo has been linked 8 different CVEs too.

Python toolkit to audit Apache HTTP Server against CVE-2026-23918 (HTTP/2 double-free RCE) and 4 related CVEs. Passive scanner with ALPN verification + read-only local auditor. No exploits.

Python

Updated: 1 week, 1 day ago
0 stars 1 fork 1 watcher
Born at : May 16, 2026, 9:18 a.m. This repo has been linked 5 different CVEs too.

Static Docsify cybersecurity news digest deployed on Vercel

HTML Python

Updated: 6 days, 8 hours ago
0 stars 0 fork 0 watcher
Born at : May 14, 2026, 1:53 p.m. This repo has been linked 3 different CVEs too.

None

Python

Updated: 1 week, 4 days ago
0 stars 0 fork 0 watcher
Born at : May 13, 2026, 8:47 a.m. This repo has been linked 1 different CVEs too.

Apache httpd mod_http2 double-free, pre-auth RCE PoC

Dockerfile Python

Updated: 1 week, 6 days ago
6 stars 1 fork 1 watcher
Born at : May 11, 2026, 2:07 p.m. This repo has been linked 1 different CVEs too.

Detection rules for CVE-2026-23918 Apache http2 RCE - Credit: stringa.ai, isec.pl

Updated: 2 weeks, 2 days ago
0 stars 0 fork 0 watcher
Born at : May 8, 2026, 4:26 a.m. This repo has been linked 3 different CVEs too.

CVE-2026-23918 Apache mod_http2 Double-Free Detector

Python

Updated: 2 weeks, 3 days ago
0 stars 0 fork 0 watcher
Born at : May 7, 2026, 5:53 a.m. This repo has been linked 1 different CVEs too.

CVE-2026-23918-Apache-HTTP-Server-DoubleFree-PoC

Python

Updated: 2 weeks, 4 days ago
0 stars 0 fork 0 watcher
Born at : May 6, 2026, 6:38 p.m. This repo has been linked 1 different CVEs too.

This is a proactive tool for security auditing. For your GitHub repository, you’ll want a description that highlights its safety (non-intrusive) and its specific utility for system administrators.

Python

Updated: 2 weeks, 4 days ago
0 stars 1 fork 1 watcher
Born at : May 6, 2026, 3:04 p.m. This repo has been linked 1 different CVEs too.

Proof-of-Concept exploit for CVE-2026-23918 (Apache mod_http2 double-free). Features multi-mode DoS (Rapid-RST, Slow-Drip) and passive RCE/vulnerability detection for Apache 2.4.66.

apache cve-2026-23918 cybersecurity denial-of-service dos double-free exploit http2 infosec python race-condition

Python

Updated: 2 weeks, 2 days ago
10 stars 3 fork 3 watcher
Born at : May 6, 2026, 1 p.m. This repo has been linked 1 different CVEs too.

None

Shell

Updated: 2 weeks, 4 days ago
0 stars 0 fork 0 watcher
Born at : May 6, 2026, 11:28 a.m. This repo has been linked 1 different CVEs too.

Apache HTTP/2 double-free vulnerability PoC (CVE-2026-23918)

apache-httpd cve dos poc vulnerability-research cve-2026-23918 cwe-415

Python Dockerfile

Updated: 2 weeks, 2 days ago
8 stars 0 fork 0 watcher
Born at : May 6, 2026, 3:45 a.m. This repo has been linked 1 different CVEs too.

Passive HTTP metadata auditor for CVE-2026-23918 exposure triage

Makefile Python

Updated: 1 week ago
0 stars 0 fork 0 watcher
Born at : May 5, 2026, 5:55 p.m. This repo has been linked 1 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-23918 vulnerability anywhere in the article.

  • The Hacker News
Four OpenClaw Flaws Enable Data Theft, Privilege Escalation, and Persistence

Cybersecurity researchers have disclosed a set of four security flaws in OpenClaw that could be chained to achieve data theft, privilege escalation, and persistence. The vulnerabilities, collectively ... Read more

Published Date: May 15, 2026 (1 week, 2 days ago)
  • The Hacker News
On-Prem Microsoft Exchange Server CVE-2026-42897 Exploited via Crafted Email

Microsoft has disclosed a new security vulnerability impacting on-premise versions of Exchange Server that it said has come under active exploitation in the wild. The vulnerability, tracked as CVE-202 ... Read more

Published Date: May 15, 2026 (1 week, 2 days ago)
  • The Hacker News
CISA Adds Cisco SD-WAN CVE-2026-20182 to KEV After Admin Access Exploits

The U.S.Cybersecurity and Infrastructure Security Agency (CISA) on Thursday added a newly disclosed vulnerability impacting Cisco Catalyst SD-WAN Controller to its Known Exploited Vulnerabilities (KEV ... Read more

Published Date: May 15, 2026 (1 week, 2 days ago)
  • The Hacker News
Cisco Catalyst SD-WAN Controller Auth Bypass Actively Exploited to Gain Admin Access

Cisco has released updates to address a maximum-severity authentication bypass flaw in Catalyst SD-WAN Controller that it said has been exploited in limited attacks. The vulnerability, tracked as CVE- ... Read more

Published Date: May 14, 2026 (1 week, 3 days ago)
  • The Hacker News
ThreatsDay Bulletin: PAN-OS RCE, Mythos cURL Bug, AI Tokenizer Attacks, and 10+ Stories

Everything is still on fire. This week feels dumb in the worst way — bad links, weak checks, fake help desks, shady forum posts, and people turning supply chain attacks into some cursed little game fo ... Read more

Published Date: May 14, 2026 (1 week, 3 days ago)
  • The Hacker News
Ghostwriter Targets Ukrainian Government With Geofenced PDF Phishing, Cobalt Strike

The Belarus-aligned threat group known as Ghostwriter has been attributed to a fresh set of attacks targeting governmental organizations in Ukraine. Active since at least 2016, Ghostwriter has been li ... Read more

Published Date: May 14, 2026 (1 week, 3 days ago)
  • The Hacker News
PraisonAI CVE-2026-44338 Auth Bypass Targeted Within Hours of Disclosure

Threat actors have been observed attempting to exploit a recently disclosed security vulnerability in PraisonAI, an open-source multi-agent orchestration framework, within four hours of public disclos ... Read more

Published Date: May 14, 2026 (1 week, 3 days ago)
  • The Hacker News
Windows Zero-Days Expose BitLocker Bypasses And CTFMON Privilege Escalation

An anonymous cybersecurity researcher who disclosed three Microsoft Defender vulnerabilities has returned with two more zero-days involving a BitLocker bypass and a privilege escalation impacting Wind ... Read more

Published Date: May 14, 2026 (1 week, 3 days ago)
  • The Hacker News
18-Year-Old NGINX Rewrite Module Flaw Enables Unauthenticated RCE

Cybersecurity researchers have disclosed multiple security vulnerabilities impacting NGINX Plus and NGINX Open, including a critical flaw that remained undetected for 18 years. The vulnerability, disc ... Read more

Published Date: May 14, 2026 (1 week, 3 days ago)
  • The Hacker News
Microsoft's MDASH AI System Finds 16 Windows Flaws Fixed in Patch Tuesday

Microsoft has unveiled a new multi-model artificial intelligence (AI)-driven system called MDASH to facilitate vulnerability discovery and remediation at scale, adding that it's being tested by some c ... Read more

Published Date: May 13, 2026 (1 week, 4 days ago)
  • The Hacker News
Mini Shai-Hulud Worm Compromises TanStack, Mistral AI, Guardrails AI & More Packages

TeamPCP, the threat actor behind the recent supply chain attack spree, has been linked to the compromise of the npm and PyPI packages from TanStack, UiPath, Mistral AI, OpenSearch, and Guardrails AI a ... Read more

Published Date: May 12, 2026 (1 week, 5 days ago)
  • The Hacker News
cPanel CVE-2026-41940 Under Active Exploitation to Deploy Filemanager Backdoor

A threat actor named Mr_Rot13 has been attributed to the exploitation of a recently disclosed critical cPanel flaw to deploy a backdoor codenamed Filemanager on compromised environments. The attack ex ... Read more

Published Date: May 11, 2026 (1 week, 6 days ago)
  • The Hacker News
Ollama Out-of-Bounds Read Vulnerability Allows Remote Process Memory Leak

Cybersecurity researchers have disclosed a critical security vulnerability in Ollama that, if successfully exploited, could allow a remote, unauthenticated attacker to leak its entire process memory. ... Read more

Published Date: May 10, 2026 (2 weeks ago)
  • The Hacker News
Critical Apache HTTP/2 Flaw (CVE-2026-23918) Enables DoS and Potential RCE

The Apache Software Foundation (ASF) has released security updates to address several security vulnerabilities in the HTTP Server, including a severe vulnerability that could potentially lead to remot ... Read more

Published Date: May 05, 2026 (2 weeks, 5 days ago)

The following table lists the changes that have been made to the CVE-2026-23918 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.

  • Initial Analysis by [email protected]

    May. 04, 2026

    Action Type Old Value New Value
    Added CPE Configuration OR *cpe:2.3:a:apache:http_server:2.4.66:*:*:*:*:*:*:*
    Added Reference Type CVE: http://www.openwall.com/lists/oss-security/2026/05/04/19 Types: Mailing List, Third Party Advisory
    Added Reference Type Apache Software Foundation: https://httpd.apache.org/security/vulnerabilities_24.html Types: Vendor Advisory
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    May. 04, 2026

    Action Type Old Value New Value
    Added Reference http://www.openwall.com/lists/oss-security/2026/05/04/19
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    May. 04, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
  • New CVE Received by [email protected]

    May. 04, 2026

    Action Type Old Value New Value
    Added Description Double Free and possible RCE vulnerability in Apache HTTP Server with the HTTP/2 protocol. This issue affects Apache HTTP Server: 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue.
    Added CWE CWE-415
    Added Reference https://httpd.apache.org/security/vulnerabilities_24.html
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.