SB2018011815 - Amazon Linux AMI update for kernel



SB2018011815 - Amazon Linux AMI update for kernel

Published: January 18, 2018

Security Bulletin ID SB2018011815
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 5
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 5 vulnerabilities.


1) Out-of-bounds read (CVE-ID: CVE-2017-17741)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local attacker to cause DoS condition on the target system.

The weakness exists due to an error in the KVM implementation in the Linux kernel. A local attacker can trigger write_mmio stack-based out-of-bounds read or possibly have unspecified other impact, related to arch/x86/kvm/x86.c and include/trace/events/kvm.h and cause the system to crash.

Successful exploitation of the vulnerability results in denial of service.

2) Security restrictions bypass (CVE-ID: CVE-2017-17448)

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local attacker to bypass security restrictions on the target system.

The weakness exists due to net/netfilter/nfnetlink_cthelper.c in the Linux kernel does not require the CAP_NET_ADMIN capability for new, get, and del operations. A local attacker can bypass intended access restrictions because the nfnl_cthelper_list data structure is shared across all net namespaces.

3) Use-after-free error (CVE-ID: CVE-2017-8824)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Clear


The vulnerability allows a local attacker to gain elevated privileges or cause DoS condition on the target system.

The weakness exists due to an error in the dccp_disconnect function in net/dccp/proto.c in the Linux kernel. A local attacker can make specially crafted AF_UNSPEC connect system call during the DCCP_LISTEN state, trigger use-after-free error and gain root privileges or cause the system to crash.

4) Race condition (CVE-ID: CVE-2017-17712)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local attacker to gain elevated privileges on the target system.

The weakness exists due to a race condition in inet->hdrincl in the raw_sendmsg() function in net/ipv4/raw.c in the Linux kernel. A local attacker can trigger uninitialized stack pointer usage and execute arbitrary code with root privileges.

Successful exploitation of the vulnerability may result in system compromise.

5) Security restrictions bypass (CVE-ID: CVE-2017-17450)

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local attacker to bypass security restrictions on the target system.

The weakness exists due to net/netfilter/xt_osf.c in the Linux kernel through does not require the CAP_NET_ADMIN capability for add_callback and remove_callback operations. A local attacker can bypass intended access restrictions because the xt_osf_fingers data structure is shared across all net namespaces.

Remediation

Install update from vendor's website.