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2 min read Intermediate Web

Insufficient Transport Layer Protection

Insufficient Transport Layer Protection

AspectDetails
DescriptionData in transit is not adequately protected by TLS, due to missing HTTPS, mixed content, weak protocols/ciphers, or no HSTS. Attackers on the network can intercept or tamper with traffic, including credentials and session tokens.
Conditions to be Vulnerable- Sensitive pages served over HTTP or with mixed content.
- HSTS not set, so users can be downgraded to HTTP.
- Deprecated protocols (SSLv3, TLS 1.0/1.1) or weak ciphers enabled.
Where to Find- Login, payment, and any page handling sensitive data.
- TLS configuration of the web server and load balancer.
- Resource references (scripts, images) loaded over HTTP.
Common Exploits- Man-in-the-middle sniffing of credentials and session cookies.
- SSL stripping / downgrade to HTTP when HSTS is missing.
- Exploiting weak ciphers/protocols (e.g. via known TLS attacks).
ExampleA login form posts to http://example.com/login. An attacker on the same Wi-Fi captures the cleartext request with credentials, since no TLS protects the submission.
How to Test1. Scan TLS config with testssl.sh or sslscan for weak protocols/ciphers.
2. Check for HTTP-to-HTTPS redirects and an Strict-Transport-Security header.
3. Inspect pages for mixed content and cleartext form submissions.
Toolstestssl.sh, sslscan, nmap (ssl-enum-ciphers), Burp Suite, SSL Labs
Mitigation- Enforce HTTPS everywhere and redirect HTTP to HTTPS.
- Enable HSTS (with preload) and disable old protocols/weak ciphers.
- Eliminate mixed content and keep TLS libraries patched.

Resources

CreditURL
OWASP WSTG - Testing for Weak Transport Layer Securityhttps://owasp.org/www-project-web-security-testing-guide/latest/4-Web_Application_Security_Testing/09-Testing_for_Weak_Cryptography/01-Testing_for_Weak_Transport_Layer_Security
OWASP Cheat Sheet - Transport Layer Securityhttps://cheatsheetseries.owasp.org/cheatsheets/Transport_Layer_Security_Cheat_Sheet.html
OWASP Cheat Sheet - HTTP Strict Transport Securityhttps://cheatsheetseries.owasp.org/cheatsheets/HTTP_Strict_Transport_Security_Cheat_Sheet.html