kernel-3.10.0-693.5.2.el7

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

Security Fix(es):

* Out-of-bounds kernel heap access vulnerability was found in xfrm, kernel's IP framework for transforming packets. An error dealing with netlink messages from an unprivileged user leads to arbitrary read/write and privilege escalation. (CVE-2017-7184, Important)

* A race condition issue leading to a use-after-free flaw was found in the way the raw packet sockets are implemented in the Linux kernel networking subsystem handling synchronization. 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-2017-1000111, Important)

* An exploitable memory corruption flaw was found in the Linux kernel. The append path can be erroneously switched from UFO to non-UFO in ip_ufo_append_data() when building an UFO packet with MSG_MORE option. If unprivileged user namespaces are available, this flaw can be exploited to gain root privileges. (CVE-2017-1000112, Important)

* A flaw was found in the Linux networking subsystem where a local attacker with CAP_NET_ADMIN capabilities could cause an out-of-bounds memory access by creating a smaller-than-expected ICMP header and sending to its destination via sendto(). (CVE-2016-8399, Moderate)

* Kernel memory corruption due to a buffer overflow was found in brcmf_cfg80211_mgmt_tx() function in Linux kernels from v3.9-rc1 to v4.13-rc1. The vulnerability can be triggered by sending a crafted NL80211_CMD_FRAME packet via netlink. This flaw is unlikely to be triggered remotely as certain userspace code is needed for this. An unprivileged local user could use this flaw to induce kernel memory corruption on the system, leading to a crash. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although it is unlikely. (CVE-2017-7541, Moderate)

* An integer overflow vulnerability in ip6_find_1stfragopt() function was found. A local attacker that has privileges (of CAP_NET_RAW) to open raw socket can cause an infinite loop inside the ip6_find_1stfragopt() function. (CVE-2017-7542, Moderate)

* A kernel data leak due to an out-of-bound read was found in the Linux kernel in inet_diag_msg_sctp{,l}addr_fill() and sctp_get_sctp_info() functions present since version 4.7-rc1 through version 4.13. A data leak happens when these functions fill in sockaddr data structures used to export socket's diagnostic information. As a result, up to 100 bytes of the slab data could be leaked to a userspace. (CVE-2017-7558, Moderate)

* The mq_notify function in the Linux kernel through 4.11.9 does not set the sock pointer to NULL upon entry into the retry logic. During a user-space close of a Netlink socket, it allows attackers to possibly cause a situation where a value may be used after being freed (use-after-free) which may lead to memory corruption or other unspecified other impact. (CVE-2017-11176, Moderate)

* A divide-by-zero vulnerability was found in the __tcp_select_window function in the Linux kernel. This can result in a kernel panic causing a local denial of service. (CVE-2017-14106, Moderate)

Asianux would like to thank Chaitin Security Research Lab for reporting
CVE-2017-7184; Willem de Bruijn for reporting CVE-2017-1000111; and Andrey
Konovalov for reporting CVE-2017-1000112. The CVE-2017-7558 issue was
discovered by Stefano Brivio (Asianux).

CVE-2016-8399
An elevation of privilege vulnerability in the kernel networking
subsystem could enable a local malicious application to execute
arbitrary code within the context of the kernel. This issue is rated
as Moderate because it first requires compromising a privileged
process and current compiler optimizations restrict access to the
vulnerable code. Product: Android. Versions: Kernel-3.10, Kernel-3.18.
Android ID: A-31349935.
CVE-2017-1000111
Linux kernel: heap out-of-bounds in AF_PACKET sockets. This new issue
is analogous to previously disclosed CVE-2016-8655. In both cases, a
socket option that changes socket state may race with safety checks in
packet_set_ring. Previously with PACKET_VERSION. This time with
PACKET_RESERVE. The solution is similar: lock the socket for the
update. This issue may be exploitable, we did not investigate further.
As this issue affects PF_PACKET sockets, it requires CAP_NET_RAW in
the process namespace. But note that with user namespaces enabled, any
process can create a namespace in which it has CAP_NET_RAW.
CVE-2017-1000112
Linux kernel: Exploitable memory corruption due to UFO to non-UFO path
switch. When building a UFO packet with MSG_MORE __ip_append_data()
calls ip_ufo_append_data() to append. However in between two send()
calls, the append path can be switched from UFO to non-UFO one, which
leads to a memory corruption. In case UFO packet lengths exceeds MTU,
copy = maxfraglen - skb->len becomes negative on the non-UFO path and
the branch to allocate new skb is taken. This triggers fragmentation
and computation of fraggap = skb_prev->len - maxfraglen. Fraggap can
exceed MTU, causing copy = datalen - transhdrlen - fraggap to become
negative. Subsequently skb_copy_and_csum_bits() writes out-of-bounds.
A similar issue is present in IPv6 code. The bug was introduced in
e89e9cf539a2 ("[IPv4/IPv6]: UFO Scatter-gather approach") on Oct 18
2005.
CVE-2017-11176
The mq_notify function in the Linux kernel through 4.11.9 does not set
the sock pointer to NULL upon entry into the retry logic. During a
user-space close of a Netlink socket, it allows attackers to cause a
denial of service (use-after-free) or possibly have unspecified other
impact.
CVE-2017-14106
The tcp_disconnect function in net/ipv4/tcp.c in the Linux kernel
before 4.12 allows local users to cause a denial of service
(__tcp_select_window divide-by-zero error and system crash) by
triggering a disconnect within a certain tcp_recvmsg code path.
CVE-2017-7184
The xfrm_replay_verify_len function in net/xfrm/xfrm_user.c in the
Linux kernel through 4.10.6 does not validate certain size data after
an XFRM_MSG_NEWAE update, which allows local users to obtain root
privileges or cause a denial of service (heap-based out-of-bounds
access) by leveraging the CAP_NET_ADMIN capability, as demonstrated
during a Pwn2Own competition at CanSecWest 2017 for the Ubuntu 16.10
linux-image-* package 4.8.0.41.52.
CVE-2017-7541
The brcmf_cfg80211_mgmt_tx function in
drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c in the
Linux kernel before 4.12.3 allows local users to cause a denial of
service (buffer overflow and system crash) or possibly gain privileges
via a crafted NL80211_CMD_FRAME Netlink packet.
CVE-2017-7542
The ip6_find_1stfragopt function in net/ipv6/output_core.c in the Linux
kernel through 4.12.3 allows local users to cause a denial of service
(integer overflow and infinite loop) by leveraging the ability to open
a raw socket.
CVE-2017-7558
** RESERVED **
This candidate has been reserved by an organization or individual that
will use it when announcing a new security problem. When the
candidate has been publicized, the details for this candidate will be
provided.