| 1. General Results, most used to calculate the result |
A | name "vfu.cz" is domain, public suffix is ".cz", top-level-domain is ".cz", top-level-domain-type is "country-code", Country is Czechia, tld-manager is "CZ.NIC, z.s.p.o", num .cz-domains preloaded: 1733 (complete: 239099)
|
A | Good: All ip addresses are public addresses
|
| Warning: Only one ip address found: vfu.cz has only one ip address.
|
| Warning: Only one ip address found: www.vfu.cz has only one ip address.
|
| Warning: No ipv6 address found. Ipv6 is the future with a lot of new features. So every domain name should have an ipv6 address. See https://en.wikipedia.org/wiki/IPv6: vfu.cz has no ipv6 address.
|
| Warning: No ipv6 address found. Ipv6 is the future with a lot of new features. So every domain name should have an ipv6 address. See https://en.wikipedia.org/wiki/IPv6: www.vfu.cz has no ipv6 address.
|
A | Good: No asked Authoritative Name Server had a timeout
|
A | https://www.vfu.cz/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de
| https://www.vfu.cz/error404.php
| Correct redirect https to https
|
A | https://www.vfu.cz/index.php
| https://www.vfu.cz/error404.php
| Correct redirect https to https
|
A | Good: destination is https
|
A | Good - only one version with Http-Status 200
|
A | Good: one preferred version: www is preferred
|
A | Good: No cookie sent via http.
|
A | Good: HSTS has preload directive
|
| Warning: HSTS preload sent, but not in Preload-List. Never send a preload directive if you don't know what preload means. Check https://hstspreload.org/ to learn the basics about the Google-Preload list. If you send a preload directive, you should **immediately** add your domain to the HSTS preload list via https://hstspreload.org/ . If Google accepts the domain, so the status is "pending": Note that new entries are hardcoded into the Chrome source code and can take several months before they reach the stable version. So you will see this message some months. If you don't want that or if you don't understand "preload", but if you send a preload directive and if you have correct A-redirects, everybody can add your domain to that list. Then you may have problems, it's not easy to undo that. So if you don't want your domain preloaded, remove the preload directive.
|
| HSTS-Preload-Status: unknown. Domain never included in the Preload-list. Check https://hstspreload.org/ to learn some basics about the Google-Preload-List.
|
A | Good: All urls with http status 200/404 have a complete Content-Type header (MediaType / MediaSubType + correct charset)
|
A | http://vfu.cz/ 195.113.198.43
| https://vfu.cz/
| Correct redirect http - https with the same domain name
|
A | http://www.vfu.cz/ 195.113.198.43
| https://www.vfu.cz/
| Correct redirect http - https with the same domain name
|
N | https://195.113.198.43/ 195.113.198.43
|
| Error - Certificate isn't trusted, RemoteCertificateNameMismatch
|
| Info: Checking all ip addresses of that domain without sending the hostname only one certificate found. Checking all ip addresses and sending the hostname only one certificate found. Both certificates are different. So that domain requires Server Name Indication (SNI), so the server is able to select the correct certificate.: Domain vfu.cz, 1 ip addresses.
|
| Info: Checking all ip addresses of that domain without sending the hostname only one certificate found. Checking all ip addresses and sending the hostname only one certificate found. Both certificates are different. So that domain requires Server Name Indication (SNI), so the server is able to select the correct certificate.: Domain www.vfu.cz, 1 ip addresses.
|
A | Good: _mta-sts TXT record found (mta-sts: Mail Transfer Agent Strict Transport Security - see RFC 8461). Domainname: _mta-sts.vfu.cz
|
A | Good: _mta-sts TXT record is valid.
|
A | Good: Subdomain mta-sts found: Subdomain-name: mta-sts.vfu.cz, ip : 195.113.198.43
|
A | Good: Certificate of subdomain is valid. mta-sts.vfu.cz, ip : 195.113.198.43
|
A | Good: /.well-known/mta-sts.txt with http status 200 found. Complete path: https://mta-sts.vfu.cz/.well-known/mta-sts.txt - ip : 195.113.198.43
|
A | Good: mta-sts.txt has the required names "version", "mode", "max_age". mta-sts.vfu.cz, ip : 195.113.198.43
|
A | Good: Minimal one mx definition found. mta-sts.vfu.cz, ip : 195.113.198.43
|
A | Excellent: Complete and valid MTA-STS found!
|
| 2. Header-Checks (Cross-Origin-* headers are alpha - started 2024-06-05) |
A | www.vfu.cz 195.113.198.43
| Content-Security-Policy
| Ok: Header without syntax errors found: default-src 'self'; form-action 'self'; img-src 'self' 'unsafe-inline' data:; style-src 'self' 'unsafe-inline' data:; script-src 'self' 'unsafe-inline' ; frame-src 'self' https://www.google.com; frame-ancestors 'none'; base-uri 'self';
|
A |
|
| Good: default-src directive only with 'none' or 'self', additional sources are blocked.
|
A |
|
| Good: default-src without 'unsafe-inline' or 'unsave-eval'.
|
A |
|
| Good: form-action directive found. That reduces the risk sending data to unwanted domains. form-action is a navigation-directive, so default-src isn't used.
|
A |
|
| Good: frame-ancestors directive found. That limits pages who are allowed to use this page in a frame / iframe / object / embed / applet. frame-ancestors is a navigation-directive, so default-src isn't used.
|
A |
|
| Good: base-uri directive found. That limits the URLs which can be used in a document's <base> element. Because it's a document directive, default-src isn't used, so an own directive is required.
|
A |
|
| Good: No object-src found, but the default-src used as fallback is defined and restricted.
|
F |
|
| Critical: script-src with 'unsafe-inline' or 'unsafe-eval' and without a nonce found. That's dangerous, don't use it. If you really need one of these unsafe directives, add a nonce.
|
A |
|
| Good: script-src without * and a scheme found.
|
A |
|
| Good: script-src without data: schema found. Why is this important? The data: schema allows hidden code injection. Insert <script src='data:application/javascript;base64,YWxlcnQoJ1hTUycpOw=='></script> in your page and see what happens.
|
A |
|
| Good: frame-src without data: defined or frame-src missing and the default-src used as fallback not allows the data: schema. That blocks hidden code injection. Insert <iframe src="data:text/html;charset=utf-8;base64,PCFET0NUWVBFIGh0bWw+PGh0bWw+PGJvZHk+PHA+YmVmb3JlPHNjcmlwdCB0eXBlPSJ0ZXh0L2phdmFzY3JpcHQiPmFsZXJ0KCdYU1MnKTwvc2NyaXB0PjxwPmFmdGVyPC9ib2R5PjwvaHRtbD4="></iframe> in your page and see what happens.
|
A |
| X-Content-Type-Options
| Ok: Header without syntax errors found: nosniff
|
A |
| Referrer-Policy
| Ok: Header without syntax errors found: strict-origin-when-cross-origin
|
A |
| Permissions-Policy
| Ok: Header without syntax errors found: accelerometer=(), camera=(), geolocation=(), gyroscope=(), magnetometer=(), microphone=(), payment=(), usb=(), fullscreen=(), sync-xhr=(), autoplay=(), encrypted-media=()
|
A |
| X-Frame-Options
| Ok: Header without syntax errors found: SAMEORIGIN
|
B |
|
| Info: Header is deprecated. May not longer work in modern browsers. SAMEORIGIN. Better solution: Use a Content-Security-Policy Header with a frame-ancestors directive. DENY - use 'none', SAMEORIGIN - use 'self'. If you want to allow some domains to frame your page, add these urls.
|
A |
| Feature-Policy
| Ok: Header without syntax errors found: accelerometer 'none'; camera 'none'; geolocation 'none'; gyroscope 'none'; magnetometer 'none'; microphone 'none'; payment 'none'; usb 'none'; fullscreen 'none'; sync-xhr 'none'; autoplay 'none'; encrypted-media 'none'
|
B |
|
| Info: Header is deprecated. May not longer work in modern browsers. accelerometer 'none'; camera 'none'; geolocation 'none'; gyroscope 'none'; magnetometer 'none'; microphone 'none'; payment 'none'; usb 'none'; fullscreen 'none'; sync-xhr 'none'; autoplay 'none'; encrypted-media 'none'
|
A |
| X-Xss-Protection
| Ok: Header without syntax errors found: 0
|
B |
|
| Info: Header is deprecated. May not longer work in modern browsers. 0
|
| 3. DNS- and NameServer - Checks |
A | Info:: 15 Root-climbing DNS Queries required to find all IPv4- and IPv6-Addresses of 2 Name Servers.
|
A | Info:: 15 Queries complete, 13 with IPv6, 2 with IPv4.
|
| Warning: Only some DNS Queries done via ipv6. IPv6 is the future, so the name servers of your name servers should have ipv6 addresses.
|
A | Good: Some ip addresses of name servers found with the minimum of two DNS Queries. One to find the TLD-Zone, one to ask the TLD-Zone.ns.muni.cz (147.251.4.33, 2001:718:801:404::33), ns1.vetuni.cz (195.113.198.35), ns.muni.cz (147.251.4.33, 2001:718:801:404::33)
|
| Ok (4 - 8):: An average of 7.5 queries per domain name server required to find all ip addresses of all name servers.
|
A | Info:: 2 different Name Servers found: ns.muni.cz, ns1.vetuni.cz, 2 Name Servers included in Delegation: ns.muni.cz, ns1.vetuni.cz, 2 Name Servers included in 1 Zone definitions: ns.muni.cz, ns1.vetuni.cz, 1 Name Servers listed in SOA.Primary: ns1.vetuni.cz.
|
A | Good: Only one SOA.Primary Name Server found.: ns1.vetuni.cz.
|
A | Good: SOA.Primary Name Server included in the delegation set.: ns1.vetuni.cz.
|
A | Good: Consistency between delegation and zone. The set of NS records served by the authoritative name servers must match those proposed for the delegation in the parent zone. Ordered list of name servers: ns.muni.cz, ns1.vetuni.cz
|
A | Good: All Name Server Domain Names have a Public Suffix.
|
A | Good: All Name Server Domain Names ending with a Public Suffix have minimal one IPv4- or IPv6 address.
|
A | Good: All Name Server ip addresses are public.
|
A | Good: Minimal 2 different name servers (public suffix and public ip address) found: 2 different Name Servers found
|
A | Good: Some Name Servers have IPv6 addresses: 1 Name Servers with IPv6 found (1 Name Servers without IPv6)
|
| Warning: All Name Servers have the same Top Level Domain / Public Suffix. If there is a problem with that Top Level Domain, your domain may be affected. Better: Use Name Servers with different top level domains.: 2 Name Servers, 1 Top Level Domain: cz
|
A | Good: Name Servers with different domain names found.: 2 different Domains found
|
| Warning: All Name Servers from the same Country / IP location.: 2 Name Servers, 1 Countries: CZ
|
A | Info: Ipv4-Subnet-list: 2 Name Servers, 2 different subnets (first Byte): 147., 195., 2 different subnets (first two Bytes): 147.251., 195.113., 2 different subnets (first three Bytes): 147.251.4., 195.113.198.
|
A | Excellent: Every Name Server IPv4-address starts with an unique Byte.
|
A | Info: IPv6-Subnet-list: 1 Name Servers with IPv6, 1 different subnets (first block): 2001:, 1 different subnets (first two blocks): 2001:0718:, 1 different subnets (first three blocks): 2001:0718:0801:, 1 different subnets (first four blocks): 2001:0718:0801:0404:
|
| Fatal: All Name Server IPv6 addresses from the same subnet.
|
A | Info: Nameserver mit different domain names found. May be a problem with DNS-Updates
|
A | Good: Nameserver supports TCP connections: 3 good Nameserver
|
A | Good: Nameserver supports Echo Capitalization: 3 good Nameserver
|
A | Good: Nameserver supports EDNS with max. 512 Byte Udp payload, message is smaller: 3 good Nameserver
|
A | Good: Nameserver has passed 10 EDNS-Checks (OP100, FLAGS, V1, V1OP100, V1FLAGS, DNSSEC, V1DNSSEC, NSID, COOKIE, CLIENTSUBNET): 2 good Nameserver
|
| Nameserver doesn't pass all EDNS-Checks: ns.muni.cz / 147.251.4.33: OP100: ok. FLAGS: ok. V1: ok. V1OP100: ok. V1FLAGS: ok. DNSSEC: ok. V1DNSSEC: ok. NSID: ok. COOKIE: fatal timeout. CLIENTSUBNET: ok.
|
A | Good: All SOA have the same Serial Number
|
| Warning: No CAA entry with issue/issuewild found, every CAA can create a certificate. Read https://en.wikipedia.org/wiki/DNS_Certification_Authority_Authorization to learn some basics about the idea of CAA. Your name server must support such an entry. Not all dns providers support CAA entries.
|
| 4. Content- and Performance-critical Checks |
| https://www.vfu.cz/error404.php
|
| Warning: Not existing ACME-file, but Server sends 200, not 404 or redirect. May be a problem creating a Letsencrypt certificate. Checking /.well-known/acme-challenge/random-filename - a http status 404 - Not Found - is expected. If your server sends content and a http status 200, the validation file (87 bytes, token, dot and the hash of the public part of the account key) may be invisible, so Letsencrypt can't validate your domain. If it is an application that sends this content, perhaps create an exception, so /.well-known/acme-challenge sends raw files. Or create a redirect to another domain and / or port 443, but your Letsencrypt client must support such a solution. Certbot: Use webroot as authenticator - https://certbot.eff.org/docs/using.html Trouble creating a certificate? Use https://community.letsencrypt.org/ to ask.
|
A | Good: Every https result with status 200 and greater 1024 Bytes is compressed (gzip, deflate, br checked).
|
| https://www.vfu.cz/ 195.113.198.43
|
| Warning: Https + http status 200 + Inline CSS / JavaScript found. Don't use inline CSS / JavaScript. These are compiled and re-used ressources, save these with a long Cache-Control max-age - header.
|
| https://www.vfu.cz/error404.php
|
| Warning: Https + http status 200 + Inline CSS / JavaScript found. Don't use inline CSS / JavaScript. These are compiled and re-used ressources, save these with a long Cache-Control max-age - header.
|
| https://195.113.198.43/ 195.113.198.43
|
| Warning: Https + http status 200 + Inline CSS / JavaScript found. Don't use inline CSS / JavaScript. These are compiled and re-used ressources, save these with a long Cache-Control max-age - header.
|
| https://www.vfu.cz/ 195.113.198.43
|
| Warning: Https result with status 200 found, Html-Content is too big. Should be max. 110 %. May contain inline CSS / JavaScript, too much comments or white space. Re-used ressources - create files with a long Cache-Control max-age header. Remove comments and white space.
|
| https://www.vfu.cz/error404.php
|
| Warning: Https result with status 200 found, Html-Content is too big. Should be max. 110 %. May contain inline CSS / JavaScript, too much comments or white space. Re-used ressources - create files with a long Cache-Control max-age header. Remove comments and white space.
|
| https://195.113.198.43/ 195.113.198.43
|
| Warning: Https result with status 200 found, Html-Content is too big. Should be max. 110 %. May contain inline CSS / JavaScript, too much comments or white space. Re-used ressources - create files with a long Cache-Control max-age header. Remove comments and white space.
|
A | Good: Every https connection via port 443 supports the http/2 protocol via ALPN.
|
A | Good: All script Elements (type text/javascript) and src-Attribute have a defer / async - Attribute. So loading and executing these JavaScripts doesn't block parsing and rendering the Html-Output.
|
| Warning: CSS / JavaScript found without Compression. Compress these ressources, gzip, deflate, br are checked. 6 external CSS / JavaScript files without GZip found - 18 with GZip, 24 complete
|
A | Good: All images with internal compression not compressed. Some Images (.png, .jpg, .jpeg, .webp, .gif) are already compressed, so an additional compression isn't helpful. 2 images (type image/png, image/jpg) found without additional GZip. Not required because these images are already compressed
|
| Warning: CSS / JavaScript files with a missing or too short Cache-Control header found. Browsers should cache and re-use these files. 15 external CSS / JavaScript files without Cache-Control-Header, 0 with Cache-Control, but no max-age, 0 with Cache-Control max-age too short (minimum 7 days), 18 with Cache-Control long enough, 33 complete.
|
| Warning: Images with a missing or too short Cache-Control header found. Browsers should cache and re-use these files. 12 image files without Cache-Control-Header, 0 with Cache-Control, but no max-age, 0 with Cache-Control max-age too short (minimum 7 days), 10 with Cache-Control long enough, 22 complete.
|
A | Good: All checked attribute values are enclosed in quotation marks (" or ').
|
A | Good: All img-elements have a valid alt-attribute.: 22 img-elements found.
|
A | Good: Domainname is not on the "Specially Designated Nationals And Blocked Persons List" (SDN). That's an US-list of individuals and companies owned or controlled by, or acting for or on behalf of, targeted countries. It also lists individuals, groups, and entities, such as terrorists and narcotics traffickers designated under programs that are not country-specific. Collectively, such individuals and companies are called "Specially Designated Nationals" or "SDNs." Their assets are blocked and U.S. persons are generally prohibited from dealing with them. So if a domain name is on that list, it's impossible to create a Letsencrypt certificate with that domain name. Check the list manual - https://www.treasury.gov/resource-center/sanctions/sdn-list/pages/default.aspx
|
A | Duration: 220783 milliseconds, 220.783 seconds
|