USN-4116-1: Linux kernel vulnerabilities

2 September 2019

Several security issues were fixed in the Linux kernel.

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Releases

Packages

Details

It was discovered that a use-after-free error existed in the block layer
subsystem of the Linux kernel when certain failure conditions occurred. A
local attacker could possibly use this to cause a denial of service (system
crash) or possibly execute arbitrary code. (CVE-2018-20856)

Amit Klein and Benny Pinkas discovered that the Linux kernel did not
sufficiently randomize IP ID values generated for connectionless networking
protocols. A remote attacker could use this to track particular Linux
devices. (CVE-2019-10638)

Praveen Pandey discovered that the Linux kernel did not properly validate
sent signals in some situations on PowerPC systems with transactional
memory disabled. A local attacker could use this to cause a denial of
service. (CVE-2019-13648)

It was discovered that the floppy driver in the Linux kernel did not
properly validate meta data, leading to a buffer overread. A local attacker
could use this to cause a denial of service (system crash).
(CVE-2019-14283)

It was discovered that the floppy driver in the Linux kernel did not
properly validate ioctl() calls, leading to a division-by-zero. A local
attacker could use this to cause a denial of service (system crash).
(CVE-2019-14284)

Jason Wang discovered that an infinite loop vulnerability existed in the
virtio net driver in the Linux kernel. A local attacker in a guest VM could
possibly use this to cause a denial of service in the host system.
(CVE-2019-3900)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

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Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 16.04

After a standard system update you need to reboot your computer to make
all the necessary changes.

ATTENTION: Due to an unavoidable ABI change the kernel updates have
been given a new version number, which requires you to recompile and
reinstall all third party kernel modules you might have installed.
Unless you manually uninstalled the standard kernel metapackages
(e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual,
linux-powerpc), a standard system upgrade will automatically perform
this as well.