SB2017041804 - Multiple vulnerabilities in Linux Kernel



SB2017041804 - Multiple vulnerabilities in Linux Kernel

Published: April 18, 2017 Updated: May 7, 2018

Security Bulletin ID SB2017041804
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 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) Resource exhaustion (CVE-ID: CVE-2017-7472)

CWE-ID: CWE-400 - Resource exhaustion

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:P/U:Clear


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

The weakness exists in the KEYS subsystem due to memory consumption. A local attacker can cause the service to crash via a series of KEY_REQKEY_DEFL_THREAD_KEYRING keyctl_set_reqkey_keyring calls.

Remediation

Install update from vendor's website.