SB2018111104 - OpenSUSE Linux update for qemu



SB2018111104 - OpenSUSE Linux update for qemu

Published: November 11, 2018

Security Bulletin ID SB2018111104
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 vulnerabilities.


1) Heap-based buffer overflow (CVE-ID: CVE-2018-11806)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

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


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

The vulnerability exists due to heap-based buffer overflow when insufficient input and validation checking of Slirp networking back-end processes by the m_cat function, as defined in the slirp/mbuf.c source code file. A remote attacker can send malformed, fragmented packets, trigger memory corruption and cause the QEMU process to crash.


2) Integer overflow (CVE-ID: CVE-2018-12617)

CWE-ID: CWE-190 - Integer overflow

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:Clear


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

The vulnerability exists due to integer overflow in qmp_guest_file_read in qga/commands-posix.c and qga/commands-win32.c in qemu-ga (aka QEMU Guest Agent). A remote attacker can send a specially crafted QMP command (including guest-file-read with a large count value) to the agent via the listening socket, cause a g_malloc0() call to trigger a segmentation fault when trying to allocate a large memory chunk and cause the service to crash.


3) Speculative Store Bypass (CVE-ID: CVE-2018-3639)

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: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 race conditions in CPU cache processing. A local attacker can conduct a side-channel attack to exploit a flaw in the speculative execution of Load and Store instructions to read privileged memory.

Note: the vulnerability is referred to as "Spectre variant 4".

Remediation

Install update from vendor's website.