If a server uses SHA512 for TLS session ticket HMAC it is vulnerable to a DoS attack where a malformed ticket will result in an OOB read which will ultimately crash. The use of SHA512 in TLS session tickets is comparatively rare as it requires a custom server callback and ticket lookup mechanism.
If a server uses SHA512 for TLS session ticket HMAC it is vulnerable to a DoS attack where a malformed ticket will result in an OOB read which will ultimately crash. The use of SHA512 in TLS session tickets is comparatively rare as it requires a custom server callback and ticket lookup mechanism.
https://www.openssl.org/news/secadv/20160922.txt