NewStart CGSL MAIN 4.05 : qemu-kvm Multiple Vulnerabilities (NS-SA-2019-0133)
Medium Nessus Plugin ID 127389
SynopsisThe remote machine is affected by multiple vulnerabilities.
DescriptionThe remote NewStart CGSL host, running version MAIN 4.05, has qemu-kvm packages installed that are affected by multiple vulnerabilities:
- An out-of-bounds read access issue was found in the VGA display emulator built into the Quick emulator (QEMU).
It could occur while reading VGA memory to update graphics display. A privileged user/process inside guest could use this flaw to crash the QEMU process on the host resulting in denial of service situation.
- An industry-wide issue was found in the way many modern microprocessor designs have implemented speculative execution of Load & Store instructions (a commonly used performance optimization). It relies on the presence of a precisely-defined instruction sequence in the privileged code as well as the fact that memory read from address to which a recent memory write has occurred may see an older value and subsequently cause an update into the microprocessor's data cache even for speculatively executed instructions that never actually commit (retire). As a result, an unprivileged attacker could use this flaw to read privileged memory by conducting targeted cache side-channel attacks.
- Quick Emulator (aka QEMU), when built with the Cirrus CLGD 54xx VGA Emulator support, allows local guest OS privileged users to cause a denial of service (out-of- bounds access and QEMU process crash) by leveraging incorrect region calculation when updating VGA display.
- An out-of-bounds read access issue was found in the VGA emulator of QEMU. It could occur in vga_draw_text routine, while updating display area for a vnc client. A privileged user inside a guest could use this flaw to crash the QEMU process resulting in DoS. (CVE-2018-5683)
Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.
SolutionUpgrade the vulnerable CGSL qemu-kvm packages. Note that updated packages may not be available yet. Please contact ZTE for more information.