Summary of mail.protonmail.ch:25 (SMTP) SSL Security Test
Provided "as is" without any warranty of any kind.
This test was made 35 days ago and may be outdated
Refresh Test
Date/Time:Sep 30th, 2026 04:50 GMT+0
Source IP/Port:185.205.70.128:25
Protocol:SMTP
Location:Strasbourg, France
Your final score:
- A
- B
- C
- F
A+
Email server's SPF and DMARC are properly set.
Good configuration
The server supports the most recent and secure TLS protocol version of TLS 1.3.
Good configuration
The tested service seems to be a SMTP.
Information
Test Results Summary for mail.protonmail.ch
- The server on the tested port is currently not prepared for post-quantum key exchange. The server’s certificate chain relies entirely on classical signature algorithms without post-quantum support. Show details.
- 1 SSL/TLS end-entity certificate detected: the first certificate is a trusted RSA 4096 bits certificate with issuer YR1 valid until December 6, 2026. 1 certificate chain detected. Show details.
- All 5 supported cipher suites are compliant with PCI DSS. The server supports only PCI DSS compliant protocols: TLSv1.2 and TLSv1.3. All supported elliptic curves are compliant with PCI DSS: P-256, P-384, P-521, X25519 and X448. No additional PCI DSS compliance issues were identified. Show details.
- 1 of 5 supported cipher suites is not compliant with HIPAA requirements (Ref. NIST SP 800-52). The server supports only HIPAA compliant protocols: TLSv1.2 and TLSv1.3. All supported elliptic curves are compliant with HIPAA: P-256, P-384, P-521, X25519 and X448. There is 1 more issue which makes the server non-compliant with HIPAA: certificate does not include an OCSP responder url. Show details.
- No issues related to industry best practices were identified. Show details.
Compliance Summary for mail.protonmail.ch
- PCI DSS Compliance Passed: All 5 supported cipher suites are compliant with PCI DSS. The server supports only PCI DSS compliant protocols: TLSv1.2 and TLSv1.3. All supported elliptic curves are compliant with PCI DSS: P-256, P-384, P-521, X25519 and X448. No additional PCI DSS compliance issues were identified.
- HIPAA Compliance Failed: 1 of 5 supported cipher suites is not compliant with HIPAA requirements (Ref. NIST SP 800-52). The server supports only HIPAA compliant protocols: TLSv1.2 and TLSv1.3. All supported elliptic curves are compliant with HIPAA: P-256, P-384, P-521, X25519 and X448. There is 1 more issue which makes the server non-compliant with HIPAA: certificate does not include an OCSP responder url.
- GDPR Compliance Passed: All 5 supported cipher suites are compliant with GDPR. The server supports only GDPR compliant protocols: TLSv1.2 and TLSv1.3. All supported elliptic curves are compliant with GDPR: P-256, P-384, P-521, X25519 and X448. No additional GDPR compliance issues were identified.
