SSL Report: k.go-firstschool.go.kr (210.102.102.189)
Assessed on:  Tue, 23 Dec 2025 03:09:21 UTC | Clear cache

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Summary
Overall Rating
B
0
20
40
60
80
100
Certificate
 
Protocol Support
 
Key Exchange
 
Cipher Strength
 

Visit our documentation page for more information, configuration guides, and books. Known issues are documented here.
This server's certificate chain is incomplete. Grade capped to B.
This server's certificate is not trusted by Java trust store (see below for details).
This server does not support TLS 1.3.  MORE INFO »
Certificate #1: RSA 2048 bits (SHA256withRSA)
Server Key and Certificate #1
Subject *.go-firstschool.go.kr
Fingerprint SHA256: 6dafe1cef7ffe0a1583c7844d1fcae62d312ce25601d9f28565f62cbabc1f0d2
Pin SHA256: ek511j67o+S+frgV0F08lPsfOzgu6fxQLZ4NFkKPY/w=
Common names *.go-firstschool.go.kr
Alternative names *.go-firstschool.go.kr go-firstschool.go.kr
Serial Number 760a8f0caaf093eff3315b3e3d4e2b64ea94e655
Valid from Mon, 20 Oct 2025 04:20:19 UTC
Valid until Fri, 20 Nov 2026 04:20:18 UTC (expires in 10 months and 27 days)
Key RSA 2048 bits (e 65537)
Weak key (Debian) No
Issuer TuringSign RSA Secure CA 2
AIA: http://public.wisekey.com/crt/tsrsasecureca2.cer
Signature algorithm SHA256withRSA
Extended Validation No
Certificate Transparency Yes (certificate)
OCSP Must Staple No
Revocation information CRL, OCSP
CRL: http://public.wisekey.com/crl/tsrsasecureca2.crl
OCSP: http://ocsp.wisekey.com
Revocation status Good (not revoked)
CRL ERROR: IOException occurred
DNS CAA No (more info)
Trusted Yes
Mozilla  Apple  Android  Java  Windows 


Additional Certificates (if supplied)
Certificates provided 1 (1920 bytes)
Chain issues Incomplete


Certification Paths
Path #1: Trusted
1 Sent by server *.go-firstschool.go.kr
Fingerprint SHA256: 6dafe1cef7ffe0a1583c7844d1fcae62d312ce25601d9f28565f62cbabc1f0d2
Pin SHA256: ek511j67o+S+frgV0F08lPsfOzgu6fxQLZ4NFkKPY/w=

RSA 2048 bits (e 65537) / SHA256withRSA
CRL ERROR: IOException occurred
2 Extra download TuringSign RSA Secure CA 2
Fingerprint SHA256: a6f9c967eb8aa9283a1ca649b87b764720e9f5c3afa81c150676f4ca36e98cf6
Pin SHA256: PEdy1ISwUVLDpnikUbhK1EtItNX5aDwLEkamk5GZosU=

RSA 4096 bits (e 65537) / SHA256withRSA
CRL ERROR: IOException occurred
3 In trust store OISTE WISeKey Global Root GB CA   Self-signed
Fingerprint SHA256: 6b9c08e86eb0f767cfad65cd98b62149e5494a67f5845e7bd1ed019f27b86bd6
Pin SHA256: FJ8u5juaXlgDJAp3DcmR/C40ReYoMcJFpJvE8fc4/5w=

RSA 2048 bits (e 65537) / SHA256withRSA
Path #1: Trusted
1 Sent by server *.go-firstschool.go.kr
Fingerprint SHA256: 6dafe1cef7ffe0a1583c7844d1fcae62d312ce25601d9f28565f62cbabc1f0d2
Pin SHA256: ek511j67o+S+frgV0F08lPsfOzgu6fxQLZ4NFkKPY/w=

RSA 2048 bits (e 65537) / SHA256withRSA
CRL ERROR: IOException occurred
2 Extra download TuringSign RSA Secure CA 2
Fingerprint SHA256: a6f9c967eb8aa9283a1ca649b87b764720e9f5c3afa81c150676f4ca36e98cf6
Pin SHA256: PEdy1ISwUVLDpnikUbhK1EtItNX5aDwLEkamk5GZosU=

RSA 4096 bits (e 65537) / SHA256withRSA
CRL ERROR: IOException occurred
3 In trust store OISTE WISeKey Global Root GB CA   Self-signed
Fingerprint SHA256: 6b9c08e86eb0f767cfad65cd98b62149e5494a67f5845e7bd1ed019f27b86bd6
Pin SHA256: FJ8u5juaXlgDJAp3DcmR/C40ReYoMcJFpJvE8fc4/5w=

RSA 2048 bits (e 65537) / SHA256withRSA
Path #1: Trusted
1 Sent by server *.go-firstschool.go.kr
Fingerprint SHA256: 6dafe1cef7ffe0a1583c7844d1fcae62d312ce25601d9f28565f62cbabc1f0d2
Pin SHA256: ek511j67o+S+frgV0F08lPsfOzgu6fxQLZ4NFkKPY/w=

RSA 2048 bits (e 65537) / SHA256withRSA
CRL ERROR: IOException occurred
2 Extra download TuringSign RSA Secure CA 2
Fingerprint SHA256: a6f9c967eb8aa9283a1ca649b87b764720e9f5c3afa81c150676f4ca36e98cf6
Pin SHA256: PEdy1ISwUVLDpnikUbhK1EtItNX5aDwLEkamk5GZosU=

RSA 4096 bits (e 65537) / SHA256withRSA
CRL ERROR: IOException occurred
3 In trust store OISTE WISeKey Global Root GB CA   Self-signed
Fingerprint SHA256: 6b9c08e86eb0f767cfad65cd98b62149e5494a67f5845e7bd1ed019f27b86bd6
Pin SHA256: FJ8u5juaXlgDJAp3DcmR/C40ReYoMcJFpJvE8fc4/5w=

RSA 2048 bits (e 65537) / SHA256withRSA
Path #1: Not trusted (path does not chain to a trusted anchor)
1 Sent by server *.go-firstschool.go.kr
Fingerprint SHA256: 6dafe1cef7ffe0a1583c7844d1fcae62d312ce25601d9f28565f62cbabc1f0d2
Pin SHA256: ek511j67o+S+frgV0F08lPsfOzgu6fxQLZ4NFkKPY/w=

RSA 2048 bits (e 65537) / SHA256withRSA
CRL ERROR: IOException occurred
2 Extra download TuringSign RSA Secure CA 2
Fingerprint SHA256: a6f9c967eb8aa9283a1ca649b87b764720e9f5c3afa81c150676f4ca36e98cf6
Pin SHA256: PEdy1ISwUVLDpnikUbhK1EtItNX5aDwLEkamk5GZosU=

RSA 4096 bits (e 65537) / SHA256withRSA
CRL ERROR: IOException occurred
3 Extra download
  Not in trust store
OISTE WISeKey Global Root GB CA   Self-signed
Fingerprint SHA256: 6b9c08e86eb0f767cfad65cd98b62149e5494a67f5845e7bd1ed019f27b86bd6
Pin SHA256: FJ8u5juaXlgDJAp3DcmR/C40ReYoMcJFpJvE8fc4/5w=

RSA 2048 bits (e 65537) / SHA256withRSA
Path #1: Trusted
1 Sent by server *.go-firstschool.go.kr
Fingerprint SHA256: 6dafe1cef7ffe0a1583c7844d1fcae62d312ce25601d9f28565f62cbabc1f0d2
Pin SHA256: ek511j67o+S+frgV0F08lPsfOzgu6fxQLZ4NFkKPY/w=

RSA 2048 bits (e 65537) / SHA256withRSA
CRL ERROR: IOException occurred
2 Extra download TuringSign RSA Secure CA 2
Fingerprint SHA256: a6f9c967eb8aa9283a1ca649b87b764720e9f5c3afa81c150676f4ca36e98cf6
Pin SHA256: PEdy1ISwUVLDpnikUbhK1EtItNX5aDwLEkamk5GZosU=

RSA 4096 bits (e 65537) / SHA256withRSA
CRL ERROR: IOException occurred
3 In trust store OISTE WISeKey Global Root GB CA   Self-signed
Fingerprint SHA256: 6b9c08e86eb0f767cfad65cd98b62149e5494a67f5845e7bd1ed019f27b86bd6
Pin SHA256: FJ8u5juaXlgDJAp3DcmR/C40ReYoMcJFpJvE8fc4/5w=

RSA 2048 bits (e 65537) / SHA256withRSA

Click here to expand

Configuration
Protocols
TLS 1.3 No
TLS 1.2 Yes
TLS 1.1 No
TLS 1.0 No
SSL 3 No
SSL 2 No


Cipher Suites
# TLS 1.2 (suites in server-preferred order)
TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (0xc030)   ECDH secp256r1 (eq. 3072 bits RSA)   FS 256
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (0xc02f)   ECDH secp256r1 (eq. 3072 bits RSA)   FS 128


Handshake Simulation
Android 4.4.2 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Android 5.0.0 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256   ECDH secp256r1  FS
Android 6.0 RSA 2048 (SHA256)   TLS 1.2 > http/1.1 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256   ECDH secp256r1  FS
Android 7.0 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Android 8.0 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Android 8.1 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Android 9.0 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
BingPreview Jan 2015 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Chrome 49 / XP SP3 RSA 2048 (SHA256)   TLS 1.2 > http/1.1 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256   ECDH secp256r1  FS
Chrome 69 / Win 7  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Chrome 70 / Win 10 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Chrome 80 / Win 10  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Firefox 31.3.0 ESR / Win 7 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256   ECDH secp256r1  FS
Firefox 47 / Win 7  R RSA 2048 (SHA256)   TLS 1.2 > http/1.1 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256   ECDH secp256r1  FS
Firefox 49 / XP SP3 RSA 2048 (SHA256)   TLS 1.2 > http/1.1 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Firefox 62 / Win 7  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Firefox 73 / Win 10  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Googlebot Feb 2018 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
IE 11 / Win 7  R Server sent fatal alert: handshake_failure
IE 11 / Win 8.1  R Server sent fatal alert: handshake_failure
IE 11 / Win Phone 8.1  R Server sent fatal alert: handshake_failure
IE 11 / Win Phone 8.1 Update  R Server sent fatal alert: handshake_failure
IE 11 / Win 10  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Edge 15 / Win 10  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Edge 16 / Win 10  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Edge 18 / Win 10  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Edge 13 / Win Phone 10  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Java 8u161 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Java 11.0.3 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Java 12.0.1 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
OpenSSL 1.0.1l  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
OpenSSL 1.0.2s  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
OpenSSL 1.1.0k  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
OpenSSL 1.1.1c  R RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Safari 6 / iOS 6.0.1 Server sent fatal alert: handshake_failure
Safari 7 / iOS 7.1  R Server sent fatal alert: handshake_failure
Safari 7 / OS X 10.9  R Server sent fatal alert: handshake_failure
Safari 8 / iOS 8.4  R Server sent fatal alert: handshake_failure
Safari 8 / OS X 10.10  R Server sent fatal alert: handshake_failure
Safari 9 / iOS 9  R RSA 2048 (SHA256)   TLS 1.2 > http/1.1 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Safari 9 / OS X 10.11  R RSA 2048 (SHA256)   TLS 1.2 > http/1.1 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Safari 10 / iOS 10  R RSA 2048 (SHA256)   TLS 1.2 > http/1.1 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Safari 10 / OS X 10.12  R RSA 2048 (SHA256)   TLS 1.2 > http/1.1 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Safari 12.1.2 / MacOS 10.14.6 Beta  R RSA 2048 (SHA256)   TLS 1.2 > http/1.1 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Safari 12.1.1 / iOS 12.3.1  R RSA 2048 (SHA256)   TLS 1.2 > http/1.1 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Apple ATS 9 / iOS 9  R RSA 2048 (SHA256)   TLS 1.2 > http/1.1 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
Yahoo Slurp Jan 2015 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
YandexBot Jan 2015 RSA 2048 (SHA256)   TLS 1.2 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384   ECDH secp256r1  FS
# Not simulated clients (Protocol mismatch)
Android 2.3.7   No SNI 2 Protocol mismatch (not simulated)
Android 4.0.4 Protocol mismatch (not simulated)
Android 4.1.1 Protocol mismatch (not simulated)
Android 4.2.2 Protocol mismatch (not simulated)
Android 4.3 Protocol mismatch (not simulated)
Baidu Jan 2015 Protocol mismatch (not simulated)
IE 6 / XP   No FS 1   No SNI 2 Protocol mismatch (not simulated)
IE 7 / Vista Protocol mismatch (not simulated)
IE 8 / XP   No FS 1   No SNI 2 Protocol mismatch (not simulated)
IE 8-10 / Win 7  R Protocol mismatch (not simulated)
IE 10 / Win Phone 8.0 Protocol mismatch (not simulated)
Java 6u45   No SNI 2 Protocol mismatch (not simulated)
Java 7u25 Protocol mismatch (not simulated)
OpenSSL 0.9.8y Protocol mismatch (not simulated)
Safari 5.1.9 / OS X 10.6.8 Protocol mismatch (not simulated)
Safari 6.0.4 / OS X 10.8.4  R Protocol mismatch (not simulated)

Click here to expand

(1) Clients that do not support Forward Secrecy (FS) are excluded when determining support for it.
(2) No support for virtual SSL hosting (SNI). Connects to the default site if the server uses SNI.
(3) Only first connection attempt simulated. Browsers sometimes retry with a lower protocol version.
(R) Denotes a reference browser or client, with which we expect better effective security.
(All) We use defaults, but some platforms do not use their best protocols and features (e.g., Java 6 & 7, older IE).
(All) Certificate trust is not checked in handshake simulation, we only perform TLS handshake.


Protocol Details
Secure Renegotiation Supported
Secure Client-Initiated Renegotiation No
Insecure Client-Initiated Renegotiation No
BEAST attack Mitigated server-side (more info)  
POODLE (SSLv3) No, SSL 3 not supported (more info)
POODLE (TLS) No (more info)
Zombie POODLE No (more info)  
GOLDENDOODLE No (more info)  
OpenSSL 0-Length No (more info)  
Sleeping POODLE No (more info)  
Downgrade attack prevention Unknown (requires support for at least two protocols, excl. SSL2)
SSL/TLS compression No
RC4 No
Heartbeat (extension) Yes
Heartbleed (vulnerability) No (more info)
Ticketbleed (vulnerability) No (more info)
OpenSSL CCS vuln. (CVE-2014-0224) No (more info)
OpenSSL Padding Oracle vuln.
(CVE-2016-2107)
No (more info)
ROBOT (vulnerability) No (more info)
Forward Secrecy Yes (with most browsers)   ROBUST (more info)
ALPN No
NPN Yes   http/1.1
Session resumption (caching) No (IDs assigned but not accepted)
Session resumption (tickets) No
OCSP stapling No
Strict Transport Security (HSTS) No
HSTS Preloading Not in: Chrome  Edge  Firefox  IE 
Public Key Pinning (HPKP) No (more info)
Public Key Pinning Report-Only No
Public Key Pinning (Static) No (more info)
Long handshake intolerance No
TLS extension intolerance No
TLS version intolerance No
Incorrect SNI alerts No
Uses common DH primes No, DHE suites not supported
DH public server param (Ys) reuse No, DHE suites not supported
ECDH public server param reuse No
Supported Named Groups secp256r1
SSL 2 handshake compatibility Yes


HTTP Requests
1 https://k.go-firstschool.go.kr/  (HTTP/1.1 200 OK)
1
Date Tue, 23 Dec 2025 03:08:24 GMT
Content-Type text/html
Content-Length 2398
Connection close
ETag "0-95e-6937c6cc"
Last-Modified Tue, 09 Dec 2025 06:50:52 GMT
Accept-Ranges bytes


Miscellaneous
Test date Tue, 23 Dec 2025 03:08:09 UTC
Test duration 71.143 seconds
HTTP status code 200
HTTP server signature -
Server hostname -


SSL Report v2.4.1