Important: kernel

Issue Overview:

Infinite recursion in ahash.c by triggering EBUSY on a full queue:
A vulnerability was found in crypto/ahash.c in the Linux kernel which allows attackers to cause a denial of service (API operation calling its own callback, and infinite recursion) by triggering EBUSY on a full queue.(CVE-2017-7618)

Time subsystem allows local users to discover real PID values:
The time subsystem in the Linux kernel, when CONFIG_TIMER_STATS is enabled, allows local users to discover real PID values (as distinguished from PID values inside a PID namespace) by reading the /proc/timer_list file, related to the print_timer function in kernel/time/timer_list.c and the __timer_stats_timer_set_start_info function in kernel/time/timer.c.(CVE-2017-5967)

Stack-based buffer overflow in sg_ioctl function:
The sg_ioctl function in drivers/scsi/sg.c in the Linux kernel allows local users to cause a denial of service (stack-based buffer overflow) or possibly have unspecified other impacts via a large command size in an SG_NEXT_CMD_LEN ioctl call, leading to out-of-bounds write access in the sg_write function. (CVE-2017-7187)

Incorrect error handling in the set_mempolicy and mbind compat syscalls in mm/mempolicy.c:
Incorrect error handling in the set_mempolicy() and mbind() compat syscalls in mm/mempolicy.c; in the Linux kernel allows local users to obtain sensitive information from uninitialized stack data by triggering failure of a certain bitmap operation. (CVE-2017-7616)

Race condition in Link Layer Control:
A race condition leading to a NULL pointer dereference was found in the Linux kernel’s Link Layer Control implementation. A local attacker with access to ping sockets could use this flaw to crash the system. (CVE-2017-2671)

Overflow in check for priv area size:
It was found that the packet_set_ring() function of the Linux kernel’s networking implementation did not properly validate certain block-size data. A local attacker with CAP_NET_RAW capability could use this flaw to trigger a buffer overflow, resulting in the crash of the system. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although we believe it is unlikely. (CVE-2017-7308)

Affected Packages:

kernel

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

New Packages:

i686:  
    perf-debuginfo-4.9.27-14.31.amzn1.i686  
    kernel-headers-4.9.27-14.31.amzn1.i686  
    kernel-debuginfo-4.9.27-14.31.amzn1.i686  
    kernel-tools-devel-4.9.27-14.31.amzn1.i686  
    kernel-tools-4.9.27-14.31.amzn1.i686  
    kernel-devel-4.9.27-14.31.amzn1.i686  
    kernel-4.9.27-14.31.amzn1.i686  
    kernel-debuginfo-common-i686-4.9.27-14.31.amzn1.i686  
    perf-4.9.27-14.31.amzn1.i686  
    kernel-tools-debuginfo-4.9.27-14.31.amzn1.i686  
  
noarch:  
    kernel-doc-4.9.27-14.31.amzn1.noarch  
  
src:  
    kernel-4.9.27-14.31.amzn1.src  
  
x86_64:  
    kernel-tools-debuginfo-4.9.27-14.31.amzn1.x86_64  
    kernel-headers-4.9.27-14.31.amzn1.x86_64  
    kernel-tools-4.9.27-14.31.amzn1.x86_64  
    perf-debuginfo-4.9.27-14.31.amzn1.x86_64  
    perf-4.9.27-14.31.amzn1.x86_64  
    kernel-tools-devel-4.9.27-14.31.amzn1.x86_64  
    kernel-debuginfo-common-x86_64-4.9.27-14.31.amzn1.x86_64  
    kernel-debuginfo-4.9.27-14.31.amzn1.x86_64  
    kernel-4.9.27-14.31.amzn1.x86_64  
    kernel-devel-4.9.27-14.31.amzn1.x86_64  

Additional References

Red Hat: CVE-2017-2671, CVE-2017-5967, CVE-2017-7187, CVE-2017-7308, CVE-2017-7616, CVE-2017-7618

Mitre: CVE-2017-2671, CVE-2017-5967, CVE-2017-7187, CVE-2017-7308, CVE-2017-7616, CVE-2017-7618