-----BEGIN PGP SIGNED MESSAGE-----
AUSCERT External Security Bulletin Redistribution
[SECURITY] [DLA 1884-1] linux security update
14 August 2019
AusCERT Security Bulletin Summary
Operating System: Debian GNU/Linux 8
Impact/Access: Root Compromise -- Existing Account
Access Privileged Data -- Existing Account
Denial of Service -- Existing Account
Reduced Security -- Existing Account
CVE Names: CVE-2019-14284 CVE-2019-14283 CVE-2019-13631
CVE-2019-10638 CVE-2019-10207 CVE-2019-3900
CVE-2019-1428 CVE-2019-1125 CVE-2018-20836
- --------------------------BEGIN INCLUDED TEXT--------------------
Package : linux
Version : 3.16.72-1
CVE ID : CVE-2017-18509 CVE-2018-20836 CVE-2019-1125 CVE-2019-3900
CVE-2019-10207 CVE-2019-10638 CVE-2019-13631 CVE-2019-14283
Several vulnerabilities have been discovered in the Linux kernel that
may lead to a privilege escalation, denial of service or information
Denis Andzakovic reported a missing type check in the IPv4 multicast
routing implementation. A user with the CAP_NET_ADMIN capability (in
any user namespace) could use this for denial-of-service (memory
corruption or crash) or possibly for privilege escalation.
chenxiang reported a race condition in libsas, the kernel
subsystem supporting Serial Attached SCSI (SAS) devices, which
could lead to a use-after-free. It is not clear how this might be
It was discovered that most x86 processors could speculatively
skip a conditional SWAPGS instruction used when entering the
kernel from user mode, and/or could speculatively execute it when
it should be skipped. This is a subtype of Spectre variant 1,
which could allow local users to obtain sensitive information from
the kernel or other processes. It has been mitigated by using
memory barriers to limit speculative execution. Systems using an
i386 kernel are not affected as the kernel does not use SWAPGS.
It was discovered that vhost drivers did not properly control the
amount of work done to service requests from guest VMs. A
malicious guest could use this to cause a denial-of-service
(unbounded CPU usage) on the host.
The syzkaller tool found a potential null dereference in various
drivers for UART-attached Bluetooth adapters. A local user with
access to a pty device or other suitable tty device could use this
for denial-of-service (BUG/oops).
Amit Klein and Benny Pinkas discovered that the generation of IP
packet IDs used a weak hash function, "jhash". This could enable
tracking individual computers as they communicate with different
remote servers and from different networks. The "siphash"
function is now used instead.
It was discovered that the gtco driver for USB input tablets could
overrun a stack buffer with constant data while parsing the device's
descriptor. A physically present user with a specially
constructed USB device could use this to cause a denial-of-service
(BUG/oops), or possibly for privilege escalation.
The syzkaller tool found a missing bounds check in the floppy disk
driver. A local user with access to a floppy disk device, with a
disk present, could use this to read kernel memory beyond the
I/O buffer, possibly obtaining sensitive information.
The syzkaller tool found a potential division-by-zero in the
floppy disk driver. A local user with access to a floppy disk
device could use this for denial-of-service (oops).
(CVE ID not yet assigned)
Denis Andzakovic reported a possible use-after-free in the
TCP sockets implementation. A local user could use this for
denial-of-service (memory corruption or crash) or possibly
for privilege escalation.
(CVE ID not yet assigned)
The netfilter conntrack subsystem used kernel addresses as
user-visible IDs, which could make it easier to exploit other
Julien Grall reported that Linux does not limit the amount of memory
which a domain will attempt to balloon out, nor limits the amount of
"foreign / grant map" memory which any individual guest can consume,
leading to denial of service conditions (for host or guests).
For Debian 8 "Jessie", these problems have been fixed in version
We recommend that you upgrade your linux packages.
Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://wiki.debian.org/LTS
- --------------------------END INCLUDED TEXT--------------------
You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to firstname.lastname@example.org
and we will forward your request to the appropriate person.
NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members. As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.
NOTE: This is only the original release of the security bulletin. It may
not be updated when updates to the original are made. If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.
Contact information for the authors of the original document is included
in the Security Bulletin above. If you have any questions or need further
information, please contact them directly.
Previous advisories and external security bulletins can be retrieved from:
Australian Computer Emergency Response Team
The University of Queensland
Internet Email: email@example.com
Facsimile: (07) 3365 7031
Telephone: (07) 3365 4417 (International: +61 7 3365 4417)
AusCERT personnel answer during Queensland business hours
which are GMT+10:00 (AEST).
On call after hours for member emergencies only.
-----BEGIN PGP SIGNATURE-----
-----END PGP SIGNATURE-----