SB2017052515 - Multiple vulnerabilities in Linux Kernel



SB2017052515 - Multiple vulnerabilities in Linux Kernel

Published: May 15, 2017

Security Bulletin ID SB2017052515
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 vulnerabilities.


1) Security restrictions bypass (CVE-ID: CVE-2016-9604)

CWE-ID: CWE-732 - Incorrect Permission Assignment for Critical Resource

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


The vulnerability allows a local attacker to write arbitrary files on the target system.

The weakness exists due to root can gain direct access to an internal keyring, such as '.dns_resolver' or '.builtin_trusted_keys' upstream, by joining it as its session keyring. A local attacker can bypass module signature verification by adding a new public key of its own devising to the keyring.

2) Information disclosure (CVE-ID: CVE-2015-8944)

CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor

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


The vulnerability allows a local attacker to obtain potentially sensitive information on the target system.

The weakness exists due to weak permissions for /proc/iomem used by the ioresources_init function in kernel/resource.c in the Linux kernel. A local attacker can read arbitrary file on the system.

3) Privilege escalation (CVE-ID: CVE-2016-7097)

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

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 the setgid bit being preserved during a setxattr call by the filesystem implementation. A local attacker can leverage the existence of a setgid program to gain group privileges.

Successful exploitation of the vulnerability results in privileges escalation.

Remediation

Install update from vendor's website.