#VU32330 Improper access control in QEMU - CVE-2015-8550

Vulnerability identifier: #VU32330

Vulnerability risk: Low

CVSSv4.0: 7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Clear]

CVE-ID: CVE-2015-8550

CWE-ID: CWE-284

Exploitation vector: Local

Exploit availability: Yes

Vulnerable software:
QEMU
Client/Desktop applications / Virtualization software

Vendor: QEMU

Description

The vulnerability allows a local privileged user to execute arbitrary code.

Xen, when used on a system providing PV backends, allows local guest OS administrators to cause a denial of service (host OS crash) or gain privileges by writing to memory shared between the frontend and backend, aka a double fetch vulnerability.

Mitigation
Install update from vendor's website.

Vulnerable software versions

QEMU: 3.1.3

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External links
https://lists.opensuse.org/opensuse-security-announce/2016-03/msg00094.html
https://lists.opensuse.org/opensuse-security-announce/2016-04/msg00045.html
https://lists.opensuse.org/opensuse-security-announce/2016-07/msg00005.html
https://www.debian.org/security/2016/dsa-3434
https://www.debian.org/security/2016/dsa-3471
https://www.debian.org/security/2016/dsa-3519
https://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html
https://www.securityfocus.com/bid/79592
https://www.securitytracker.com/id/1034479
https://xenbits.xen.org/xsa/advisory-155.html
https://security.gentoo.org/glsa/201604-03

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.