[El-errata] New updates available via Ksplice (ELSA-2015-3055)

[Errata Announcements for Oracle Linux]

Synopsis: ELSA-2015-3055 can now be patched using Ksplice
CVEs: CVE-2014-8133 CVE-2014-9683 CVE-2015-0239 CVE-2015-3339

Users with Oracle Linux Premier Support can now use Ksplice to patch
against the latest Oracle Security Advisory, ELSA-2015-3055.

INSTALLING THE UPDATES

We recommend that all users of Ksplice Uptrack on EL 6 install these
updates.

On systems that have "autoinstall = yes" in /etc/uptrack/uptrack.conf,
these updates will be installed automatically and you do not need to
take any action.

Alternatively, you can install these updates by running:

# /usr/sbin/uptrack-upgrade -y


DESCRIPTION

* Kernel hang on UDP flood with wrong checksums.

A flaw in the UDP handling of wrong checksums could lead to a kernel hang
under a UDP flood attack.  A remote attacker could use this flaw to cause a
denial-of-service.


* CVE-2014-9683: Out-of-bounds memory write in eCryptfs when decoding a file name.

A lack of input validation when decoding a file name in the eCryptfs driver
could lead to an out-of-bounds memory write of one zero byte, potentially
causing a kernel panic.  A local user could use a specially crafted
eCryptfs filesystem to cause a denial-of-service.


* CVE-2015-3339: Privilege escalation due to race condition between execve and chown.

The execve() syscall can race with inode attribute changes made by chown().
This race condition could result in execve() setting uid/gid to the new
owner, leading to privilege escalation.


* CVE-2014-8133: Information leak in thread area of 32-bit KVM guests.

The espfix implementation which prevents kernel information leaking to
unprivileged guests can be bypassed by creating a custom thread area. A
local unprivileged user could potentially use this flaw to leak stack
addresses.


* CVE-2015-0239: Privilege escalation in KVM sysenter emulation.

The KVM emulation of the sysenter instruction does not validate 16-bit
code segments which can allow a local attacker to potentially elevate
privileges.


* Improved fix to CVE-2014-8133: Information leak in thread area of 32-bit KVM guests.

The espfix implementation which prevents kernel information leaking to
unprivileged guests can be bypassed by creating a custom thread area. A
local unprivileged user could potentially use this flaw to leak stack
addresses.

SUPPORT

Ksplice support is available at ksplice-support_ww at oracle.com.