ALAS-2017-914


Amazon Linux AMI Security Advisory: ALAS-2017-914
Advisory Release Date: 2017-10-26 23:04 Pacific
Severity: Important

Issue Overview:

stack buffer overflow in the native Bluetooth stack
A stack buffer overflow flaw was found in the way the Bluetooth subsystem of the Linux kernel processed pending L2CAP configuration responses from a client. On systems with the stack protection feature enabled in the kernel (CONFIG_CC_STACKPROTECTOR=y, which is enabled on all architectures other than s390x and ppc64[le]), an unauthenticated attacker able to initiate a connection to a system via Bluetooth could use this flaw to crash the system. Due to the nature of the stack protection feature, code execution cannot be fully ruled out, although we believe it is unlikely. On systems without the stack protection feature (ppc64[le]; the Bluetooth modules are not built on s390x), an unauthenticated attacker able to initiate a connection to a system via Bluetooth could use this flaw to remotely execute arbitrary code on the system with ring 0 (kernel) privileges. (CVE-2017-1000251 )

dereferencing NULL payload with nonzero length
A flaw was found in the implementation of associative arrays where the add_key systemcall and KEYCTL_UPDATE operations allowed for a NULL payload with a nonzero length. When accessing the payload within this length parameters value, an unprivileged user could trivially cause a NULL pointer dereference (kernel oops). (CVE-2017-15274 )

xfs: unprivileged user kernel oops
A flaw was found where the XFS filesystem code mishandles a user-settable inode flag in the Linux kernel prior to 4.14-rc1. This can cause a local denial of service via a kernel panic.(CVE-2017-14340 )

Information leak in the scsi driver
The sg_ioctl() function in 'drivers/scsi/sg.c' in the Linux kernel, from version 4.12-rc1 to 4.14-rc2, allows local users to obtain sensitive information from uninitialized kernel heap-memory locations via an SG_GET_REQUEST_TABLE ioctl call for '/dev/sg0'. (CVE-2017-14991 )

kvm: nVMX: L2 guest could access hardware(L0) CR8 register
Linux kernel built with the KVM visualization support (CONFIG_KVM), with nested visualization (nVMX) feature enabled (nested=1), is vulnerable to a crash due to disabled external interrupts. As L2 guest could access (r/w) hardware CR8 register of the host(L0). In a nested visualization setup, L2 guest user could use this flaw to potentially crash the host(L0) resulting in DoS. (CVE-2017-12154 )


Affected Packages:

kernel


Issue Correction:
Run yum update kernel to update your system.

New Packages:
i686:
    kernel-headers-4.9.58-18.51.amzn1.i686
    perf-4.9.58-18.51.amzn1.i686
    perf-debuginfo-4.9.58-18.51.amzn1.i686
    kernel-4.9.58-18.51.amzn1.i686
    kernel-devel-4.9.58-18.51.amzn1.i686
    kernel-tools-debuginfo-4.9.58-18.51.amzn1.i686
    kernel-debuginfo-4.9.58-18.51.amzn1.i686
    kernel-tools-4.9.58-18.51.amzn1.i686
    kernel-tools-devel-4.9.58-18.51.amzn1.i686
    kernel-debuginfo-common-i686-4.9.58-18.51.amzn1.i686

noarch:
    kernel-doc-4.9.58-18.51.amzn1.noarch

src:
    kernel-4.9.58-18.51.amzn1.src

x86_64:
    kernel-tools-debuginfo-4.9.58-18.51.amzn1.x86_64
    kernel-debuginfo-common-x86_64-4.9.58-18.51.amzn1.x86_64
    kernel-devel-4.9.58-18.51.amzn1.x86_64
    kernel-debuginfo-4.9.58-18.51.amzn1.x86_64
    kernel-4.9.58-18.51.amzn1.x86_64
    perf-debuginfo-4.9.58-18.51.amzn1.x86_64
    kernel-tools-devel-4.9.58-18.51.amzn1.x86_64
    kernel-tools-4.9.58-18.51.amzn1.x86_64
    perf-4.9.58-18.51.amzn1.x86_64
    kernel-headers-4.9.58-18.51.amzn1.x86_64