Rank #3,488Updated November 10, 2026
t.cn
Sina Visitor System
The site runs on Content Security Policy, HSTS. Its email security grade is F. Its SSL certificate is issued by DigiCert, Inc. and is valid for 51 more days.
- Domain age
- —
- Technologies
- 2
- Email security
- F
- SSL days left
- 51
DNS records
| Type | Value | TTL |
|---|---|---|
| A | 123.56.139.83 | 60 |
| MX | mx.sina.net 10 | 60 |
| NS | ns4.sina.com.cn | 60 |
| NS | ns1.sina.com.cn | 60 |
| NS | ns3.sina.com.cn | 60 |
| NS | ns2.sina.com.cn | 60 |
| AAAA | 2408:4000:200::3b4 | 60 |
Technology stack
Security
SSL certificate
| Valid | Valid |
|---|---|
| Issuer | US, GeoTrust G2 TLS CN RSA4096 SHA256 2022 CA1, DigiCert, Inc. |
| Expires | December 31, 2026 |
| Days remaining | 51 |
| Protocol | TLSv1.3 |
| Names | sina.com, m.beacon.sina.com.cn, img.star.weibo.com, wk.impress.sinaimg.cn, www.sina.com, cre.dp.sina.cn, i.sso.sina.com.cn, img.dmp.sina.com.cn, int.dpool.sina.com.cn, sina.com.cn, sinaimg.cn, vip.stock.finance.sina.com.cn |
Email security
FScore 5/100 across SPF, DMARC, DKIM, MTA-STS and BIMI.
- badNo SPF record. Anyone can send email that claims to come from t.cn.
- badNo DMARC record. Receivers have no instructions for mail that fails SPF and DKIM, and you get no reports about who sends as your domain.
- warnNo DKIM key found at common selectors (google, selector1, selector2, default, k1, k2, s1, s2, ...). DKIM may still use a custom selector we cannot guess.
- warnNo MTA-STS: mail sent to you can be downgraded to an unencrypted connection.
- warnNo TLS-RPT record, so you won't hear about failed encrypted deliveries.
- warnNo BIMI record (optional: shows your logo next to your emails in supporting inboxes).
- good1 MX record(s) found.
Homepage metadata
| Title | Sina Visitor System |
|---|---|
| Indexable | Yes |
| Word count | 0 |
About t.cn
What technology does t.cn use?
We detected 2 technologies on t.cn, including Content Security Policy, HSTS.
Does t.cn protect its email with SPF and DMARC?
t.cn scores 5/100 (grade F) for email security. No SPF record. Anyone can send email that claims to come from t.cn. No DMARC record. Receivers have no instructions for mail that fails SPF and DKIM, and you get no reports about who sends as your domain.
What are the name servers of t.cn?
t.cn uses ns4.sina.com.cn, ns1.sina.com.cn, ns3.sina.com.cn, ns2.sina.com.cn.