Insecure TLS_DHE_PSK_WITH_NULL_SHA256
- IANA name:
- TLS_DHE_PSK_WITH_NULL_SHA256
- OpenSSL name:
- DHE-PSK-NULL-SHA256
- GnuTLS name:
- TLS_DHE_PSK_NULL_SHA256
- Hex code:
- 0x00, 0xB4
- TLS Version(s):
- TLS1.0, TLS1.1, TLS1.2, TLS1.3
- Protocol:
- Transport Layer Security (TLS)
- Key Exchange:
- PFS Diffie-Hellman Ephemeral (DHE)
- Authentication:
- Pre-Shared Key (PSK)
- Encryption:
- NULL Encryption (NULL)
- Hash:
- HMAC Secure Hash Algorithm 256 (SHA256)
- Included in RFC:
- Machine-readable:
- application/json
The so-called DHEat Attack affects cryptographic protocols using the Diffie Hellman key exchange (incl. TLS). According to its authors, it exploits a protocol particularity that may allow attackers to perform a DoS attack "with a low-bandwidth network connection without authentication, privilege, or user interaction."
The so-called Raccoon Attack affects the specifications of TLS 1.2 and below when using a DH(E) key exchange. According to the researchers, while very hard to exploit, in rare circumstances this timing attack allows attackers to decrypt the connection between users and the server. A fix has been introduced in the TLS 1.3 specification.
This cipher suite uses no encryption at all. Hence, it does not provide confidentiality protection.