Advisories ยป MGASA-2016-0415

Updated kernel packages fixes security vulnerabilities

Publication date: 08 Dec 2016
Type: security
Affected Mageia releases : 5
CVE: CVE-2016-8645 , CVE-2016-8650 , CVE-2016-8655 , CVE-2016-9756 , CVE-2016-9793


This update is based on upstream 4.4.36 and fixes at least the following
security issues:

The TCP stack in the Linux kernel before 4.8.10 mishandles skb truncation,
which allows local users to cause a denial of service (system crash) via
a crafted application that makes sendto system calls, related to 
net/ipv4/tcp_ipv4.c and net/ipv6/tcp_ipv6.c (CVE-2016-8645).

The mpi_powm function in lib/mpi/mpi-pow.c in the Linux kernel through
4.8.11 does not ensure that memory is allocated for limb data, which allows
local users to cause a denial of service (stack memory corruption and panic)
via an add_key system call for an RSA key with a zero exponent

A race condition issue leading to a use-after-free flaw was found in the
way the raw packet sockets implementation in the Linux kernel networking
subsystem handled synchronization while creating the TPACKET_V3 ring
buffer. A local user able to open a raw packet socket (requires the
CAP_NET_RAW capability) could use this flaw to elevate their privileges
on the system (CVE-2016-8655).

Linux kernel built with the Kernel-based Virtual Machine(CONFIG_KVM)
support is vulnerable to an information leakage issue. It could occur
on x86 platform, while emulating instructions in 32bit mode. A 
user/process could use this flaw to leak host kernel memory bytes

A bug in SO_{SND|RCV}BUFFORCE setsockopt() implementation allows
CAP_NET_ADMIN users to set negative sk_sndbuf or sk_rcvbuf values.
A user could use this flaw to cause various memory corruptions,
crashes and OOM (CVE-2016-9793).

For other fixes in this update, see the referenced changelogs.