openmathbooks.org

.org crawl

First seen 2026-04-23 · Last seen 2026-05-14 · ok HTTP/1.1 200 1326 ms crawled 2026-05-17

US · 104.21.42.206 · AS13335 Cloudflare, Inc.

Reputation 95/100 weak security headers

sector nonprofit type blog

HTML metadata

Title: OpenMathBooks.org | OpenMathBooks
Description: Website for the OpenMathBooks project
Language: en-US
Generator: Jekyll v3.10.0
Canonical: https://openmathbooks.org/

Open Graph

url: http://openmathbooks.org/
title: OpenMathBooks.org
locale: en_US
site name: OpenMathBooks
description: Website for the OpenMathBooks project

Technology

CDN: Cloudflare

Analytics

Cloudflare Insights

Third-party hosts loaded (2)

cdnjs.cloudflare.com×1
static.cloudflareinsights.com×1

Registration

Registrar

NameCheap, Inc.

Created

2017-07-21

Expires

2026-07-21 61 days left

Updated

2025-09-04

Name servers

barbara.ns.cloudflare.com
henry.ns.cloudflare.com

DNS records live

NS

barbara.ns.cloudflare.com
henry.ns.cloudflare.com

TXT

MAltYWlsLm9wZW5tYXRoYm9va3Mub3JnLgo=

Verified for

Google

Email authentication no MX

SPF

not published

DMARC

not published

DKIM

default: v=DKIM1; k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAuxVHUAYJCz5vZ41O95ypyrn4pZmGOn8izIocLrh1HIIIMGUjsfRB8Lsyfeayjh3C36h/MiIAOzEjcN…

selectors probed

Certificate (current)

WE1

from 2026-05-14 to 2026-08-12

Expires in 83 days

Full certificate history on crt.sh ↗

HTTP security headers

Header hygiene 30/100 Checked live page: https://openmathbooks.org/

findings

missing HSTS
missing Content Security Policy
missing frame protection
missing content type protection
missing Referrer Policy
missing Permissions Policy

Linked from (1)

oscarlevin.com×2