Ubuntu Security Notice 2823-1 – It was discovered that the SCTP protocol implementation in the Linux kernel performed an incorrect sequence of protocol-initialization steps. A local attacker could use this to cause a denial of service (system crash). Dmitry Vyukov discovered that the Linux kernel’s keyring handler attempted to garbage collect incompletely instantiated keys. A local unprivileged attacker could use this to cause a denial of service (system crash). Various other issues were also addressed.