SB2019070304 - Security restrictions bypass in QEMU



SB2019070304 - Security restrictions bypass in QEMU

Published: July 3, 2019 Updated: April 28, 2020

Security Bulletin ID SB2019070304
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

Medium 33% Low 67%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 vulnerabilities.


1) Improper access control (CVE-ID: CVE-2019-13164)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/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 gain unauthorized access to sensitive information.

The vulnerability exists due to qemu-bridge-helper.c does not ensure that a network interface name (obtained from bridge.conf or a --br=bridge option) is limited to the IFNAMSIZ size. A local attacker can create a tap device and attach it to a denied bridge interface, bypass the Access Control List (ACL) and get access to confidential data transmitted on the bridge.


2) Buffer overflow (CVE-ID: CVE-2019-15034)

CWE-ID: CWE-119 - Memory corruption

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 user to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error within the hw/display/bochs-display.c in QEMU due to application does not ensure a sufficient PCI config space allocation. A local user can trigger a buffer overflow and escalate privileges on the system.


3) Use-after-free (CVE-ID: CVE-2019-15890)

CWE-ID: CWE-416 - Use After Free

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:U/U:Green


The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists in "ip_reass()" routine in "ip_input.c" file while reassembling incoming packets, if the first fragment is bigger than the m->m_dat[] buffer. A remote attacker can send a specially crafted packet and cause the application to crash.



Remediation

Install update from vendor's website.