NULL dereference in SSL_CIPHER_find() function on unknown cipher ID

Issue summary: If an application using the SSL_CIPHER_find() function in

a QUIC protocol client or server receives an unknown cipher suite from

the peer, a NULL dereference occurs.

Impact summary: A NULL pointer dereference leads to abnormal termination of

the running process causing Denial of Service.

Some applications call SSL_CIPHER_find() from the client_hello_cb callback

on the cipher ID received from the peer. If this is done with an SSL object

implementing the QUIC protocol, NULL pointer dereference will happen if

the examined cipher ID is unknown or unsupported.

As it is not very common to call this function in applications using the QUIC

protocol and the worst outcome is Denial of Service, the issue was assessed

as Low severity.

The vulnerable code was introduced in the 3.2 version with the addition

of the QUIC protocol support.

The FIPS modules in 3.6, 3.5, 3.4 and 3.3 are not affected by this issue,

as the QUIC implementation is outside the OpenSSL FIPS module boundary.

OpenSSL 3.6, 3.5, 3.4 and 3.3 are vulnerable to this issue.

OpenSSL 3.0, 1.1.1 and 1.0.2 are not affected by this issue.