SB2019032611 - Amazon Linux AMI update for kernel



SB2019032611 - Amazon Linux AMI update for kernel

Published: March 26, 2019 Updated: May 22, 2019

Security Bulletin ID SB2019032611
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 50% Low 50%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 vulnerabilities.


1) NULL pointer dereference (CVE-ID: CVE-2019-9213)

CWE-ID: CWE-476 - NULL Pointer Dereference

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:A/U:Clear


The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dreference error in expand_downwards() in mm/mmap.c that does not check for the mmap minimum address, which makes it easier for attackers to exploit kernel NULL pointer dereferences on non-SMAP platforms. This is related to a capability check for the wrong task. A local user can perform a denial of service (DoS) attack.


2) Memory leak (CVE-ID: CVE-2019-8980)

CWE-ID: CWE-401 - Missing release of memory after effective lifetime

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


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper memory operations in the kernel_read_file function, as defined in the fs/exec.c source code file. A remote attacker can send malicious file that triggers vfs_read failures and memory leak condition and perform a denial of service attack.


Remediation

Install update from vendor's website.