Kernel security update: Virtuozzo ReadyKernel patch 49.0 for Virtuozzo 7.0.7 and 7.0.7 HF2

The cumulative Virtuozzo ReadyKernel patch was updated with security and stability fixes. The patch applies to Virtuozzo 7.0 kernels 3.10.0-693.17.1.vz7.43.10 (7.0.7) and 3.10.0-693.21.1.vz7.46.7 (7.0.7 HF2).
Vulnerability id: CVE-2017-17448
It was discovered that nfnl_cthelper_list structure was accessible to any user with CAP_NET_ADMIN capability in a network namespace. An unprivileged local user could exploit that to affect netfilter conntrack helpers on the host.

Vulnerability id: CVE-2017-17449
It was discovered that a nlmon link inside a child network namespace was not restricted to that namespace. An unprivileged local user could exploit that to monitor system-wide netlink activity.

Vulnerability id: CVE-2017-17450
It was discovered that xt_osf_fingers data structure was accessible from any network namespace. This allowed unprivileged local users to bypass intended access restrictions and modify the system-wide OS fingerprint list used by specific iptables rules.

Vulnerability id: CVE-2017-17807
The KEYS subsystem omitted an access-control check when writing a key to the default keyring of the current task, allowing a local user to bypass security checks for the keyring. This compromised the validity of the keyring for those who relied on it.

Vulnerability id: PSBM-83692
If ‘dccp_ipv6’ module was loaded on the host, a local unprivileged user could trigger a kernel crash in dccp_write_xmit() or inet_csk_get_port() using a specially crafted sequence of system calls.