(RHSA-2016:1633) Important: kernel security and bug fix update

The kernel packages contain the Linux kernel, the core of any Linux
operating system.

It was found that the RFC 5961 challenge ACK rate limiting as implemented
in the Linux kernel’s networking subsystem allowed an off-path attacker to
leak certain information about a given connection by creating congestion on
the global challenge ACK rate limit counter and then measuring the changes
by probing packets. An off-path attacker could use this flaw to either
terminate TCP connection and/or inject payload into non-secured TCP
connection between two endpoints on the network. (CVE-2016-5696, Important)

Red Hat would like to thank Yue Cao from Cyber Security Group in the CS department of University of California, Riverside, for reporting this issue.