SB2019021817 - Ubuntu update for Linux kernel 



SB2019021817 - Ubuntu update for Linux kernel

Published: February 18, 2019

Security Bulletin ID SB2019021817
Severity
Low
Patch available
YES
Number of vulnerabilities 4
Exploitation vector Adjecent network
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 4 secuirty vulnerabilities.


1) Race condition (CVE-ID: CVE-2018-14625)

The vulnerability allows a local attacker to obtain potentially sensitive information.

The weakness exists due to a race condition between connect() and close() function. A local attacker can use the AF_VSOCK protocol to obtain sensitive information possibly intercept or corrupt AF_VSOCK messages destined to other clients.

2) Use-after-free error (CVE-ID: CVE-2018-16882)

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

The vulnerability exists due to in nested_get_vmcs12_pages(), in case of an error while processing posted interrupt address, it unmaps the 'pi_desc_page' without resetting 'pi_desc' descriptor address which is latter used in pi_test_and_clear_on(). An adjacent attacker can use a malicious container to trigger use-after-free error and crash the host kernel resulting in DoS OR potentially gain privileged access to a system.


3) Null pointer dereference (CVE-ID: CVE-2018-19407)

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

The vulnerability exists in the vcpu_scan_ioapic function, as defined in the arch/x86/kvm/x86.c source code file due to the failure of the I/O Advanced Programmable Interrupt Controller (I/O APIC) to initialize. A local attacker can access the system and execute an application that submits malicious system calls, trigger a NULL pointer dereference, which could result in a DoS condition.


4) Memory leak (CVE-ID: CVE-2018-19854)

The vulnerability allows a local attacker to perform DoS attack on the target system.

The vulnerability exists due to crypto_report_one() and related functions in crypto/crypto_user.c (the crypto user configuration API) do not fully initialize structures that are copied to userspace. A local attacker can trigger memory leak and perform denial of service attack.

Remediation

Install update from vendor's website.