[SECURITY] [DSA 3981-1] linux security update

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Debian Security Advisory DSA-3981-1 [email protected]
https://www.debian.org/security/ Salvatore Bonaccorso
September 20, 2017 https://www.debian.org/security/faq

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Package : linux
CVE ID : CVE-2017-7518 CVE-2017-7558 CVE-2017-10661 CVE-2017-11600
CVE-2017-12134 CVE-2017-12146 CVE-2017-12153 CVE-2017-12154
CVE-2017-14106 CVE-2017-14140 CVE-2017-14156 CVE-2017-14340
CVE-2017-14489 CVE-2017-14497 CVE-2017-1000111 CVE-2017-1000112
CVE-2017-1000251 CVE-2017-1000252 CVE-2017-1000370 CVE-2017-1000371
CVE-2017-1000380
Debian Bug : 866511 875881

Several vulnerabilities have been discovered in the Linux kernel that
may lead to privilege escalation, denial of service or information
leaks.

CVE-2017-7518

Andy Lutomirski discovered that KVM is prone to an incorrect debug
exception (#DB) error occurring while emulating a syscall
instruction. A process inside a guest can take advantage of this
flaw for privilege escalation inside a guest.

CVE-2017-7558 (stretch only)

Stefano Brivio of Red Hat discovered that the SCTP subsystem is
prone to a data leak vulnerability due to an out-of-bounds read
flaw, allowing to leak up to 100 uninitialized bytes to userspace.

CVE-2017-10661 (jessie only)

Dmitry Vyukov of Google reported that the timerfd facility does
not properly handle certain concurrent operations on a single file
descriptor.  This allows a local attacker to cause a denial of
service or potentially execute arbitrary code.

CVE-2017-11600

Bo Zhang reported that the xfrm subsystem does not properly
validate one of the parameters to a netlink message. Local users
with the CAP_NET_ADMIN capability can use this to cause a denial
of service or potentially to execute arbitrary code.

CVE-2017-12134 / #866511 / XSA-229

Jan H. Schoenherr of Amazon discovered that when Linux is running
in a Xen PV domain on an x86 system, it may incorrectly merge
block I/O requests.  A buggy or malicious guest may trigger this
bug in dom0 or a PV driver domain, causing a denial of service or
potentially execution of arbitrary code.

This issue can be mitigated by disabling merges on the underlying
back-end block devices, e.g.:
    echo 2 > /sys/block/nvme0n1/queue/nomerges

CVE-2017-12146 (stretch only)

Adrian Salido of Google reported a race condition in access to the
"driver_override" attribute for platform devices in sysfs. If
unprivileged users are permitted to access this attribute, this
might allow them to gain privileges.

CVE-2017-12153

bo Zhang reported that the cfg80211 (wifi) subsystem does not
properly validate the parameters to a netlink message. Local users
with the CAP_NET_ADMIN capability (in any user namespace with a
wifi device) can use this to cause a denial of service.

CVE-2017-12154

Jim Mattson of Google reported that the KVM implementation for
Intel x86 processors did not correctly handle certain nested
hypervisor configurations. A malicious guest (or nested guest in a
suitable L1 hypervisor) could use this for denial of service.

CVE-2017-14106

Andrey Konovalov discovered that a user-triggerable division by
zero in the tcp_disconnect() function could result in local denial
of service.

CVE-2017-14140

Otto Ebeling reported that the move_pages() system call performed
insufficient validation of the UIDs of the calling and target
processes, resulting in a partial ASLR bypass. This made it easier
for local users to exploit vulnerabilities in programs installed
with the set-UID permission bit set.

CVE-2017-14156

"sohu0106" reported an information leak in the atyfb video driver.
A local user with access to a framebuffer device handled by this
driver could use this to obtain sensitive information.

CVE-2017-14340

Richard Wareing discovered that the XFS implementation allows the
creation of files with the "realtime" flag on a filesystem with no
realtime device, which can result in a crash (oops). A local user
with access to an XFS filesystem that does not have a realtime
device can use this for denial of service.

CVE-2017-14489

ChunYu Wang of Red Hat discovered that the iSCSI subsystem does not
properly validate the length of a netlink message, leading to
memory corruption. A local user with permission to manage iSCSI
devices can use this for denial of service or possibly to execute
arbitrary code.

CVE-2017-14497 (stretch only)

Benjamin Poirier of SUSE reported that vnet headers are not
properly handled within the tpacket_rcv() function in the raw
packet (af_packet) feature. A local user with the CAP_NET_RAW
capability can take advantage of this flaw to cause a denial of
service (buffer overflow, and disk and memory corruption) or have
other impact.

CVE-2017-1000111

Andrey Konovalov of Google reported a race condition in the raw
packet (af_packet) feature. Local users with the CAP_NET_RAW
capability can use this for denial of service or possibly to
execute arbitrary code.

CVE-2017-1000112

Andrey Konovalov of Google reported a race condition flaw in the
UDP Fragmentation Offload (UFO) code. A local user can use this
flaw for denial of service or possibly to execute arbitrary code.

CVE-2017-1000251 / #875881

Armis Labs discovered that the Bluetooth subsystem does not
properly validate L2CAP configuration responses, leading to a
stack buffer overflow. This is one of several vulnerabilities
dubbed "Blueborne". A nearby attacker can use this to cause a
denial of service or possibly to execute arbitrary code on a
system with Bluetooth enabled.

CVE-2017-1000252 (stretch only)

Jan H. Schoenherr of Amazon reported that the KVM implementation
for Intel x86 processors did not correctly validate interrupt
injection requests. A local user with permission to use KVM could
use this for denial of service.

CVE-2017-1000370

The Qualys Research Labs reported that a large argument or
environment list can result in ASLR bypass for 32-bit PIE binaries.

CVE-2017-1000371

The Qualys Research Labs reported that a large argument
orenvironment list can result in a stack/heap clash for 32-bit
PIE binaries.

CVE-2017-1000380

Alexander Potapenko of Google reported a race condition in the ALSA
(sound) timer driver, leading to an information leak. A local user
with permission to access sound devices could use this to obtain
sensitive information.

Debian disables unprivileged user namespaces by default, but if they
are enabled (via the kernel.unprivileged_userns_clone sysctl) then
CVE-2017-11600, CVE-2017-14497 and CVE-2017-1000111 can be exploited
by any local user.

For the oldstable distribution (jessie), these problems have been fixed
in version 3.16.43-2+deb8u5.

For the stable distribution (stretch), these problems have been fixed in
version 4.9.30-2+deb9u5.

We recommend that you upgrade your linux packages.

Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://www.debian.org/security/

Mailing list: [email protected]