Vulnerability identifier: #VU27542

Vulnerability risk: Medium

CVSSv3.1: 7.1 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:U/RL:U/RC:C]

CVE-ID: CVE-2020-10717

CWE-ID: CWE-399

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
QEMU
Client/Desktop applications / Virtualization software

Vendor: QEMU

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper management of internal resources with the virtio-fs shared file system daemon (virtiofsd) implementation of the QEMU. Virtio-fs is meant to share a host file system directory with a guest via virtio-fs device. If the guest opens the maximum number of file descriptors under the shared directory, a denial of service may occur. This flaw allows a guest user/process to cause this denial of service on the host.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

QEMU: 4.0.0 - 5.0.0

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External links
http://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-10717
http://www.openwall.com/lists/oss-security/2020/05/04/1
http://lists.gnu.org/archive/html/qemu-devel/2020-05/msg00143.html
http://lists.gnu.org/archive/html/qemu-devel/2020-05/msg00141.html

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.