SB2018061802 - Denial of service in QEMU
Published: June 18, 2018 Updated: July 30, 2018
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 secuirty vulnerabilities.
1) Heap-based buffer overflow (CVE-ID: CVE-2018-11806)
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)
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.
Remediation
Install update from vendor's website.