A Bleichenbacher type side-channel based padding oracle attack was found in the way nettle handles endian conversion of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run a process on the same physical core as the victim process, could use this flaw extract plaintext or in some cases downgrade any TLS connections to a vulnerable server. http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-16869