CVE-2020-10761

Severity: medium (CVSS 5.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-06-09 · updated 2026-06-17
Weakness: CWE-617

Description

An assertion failure issue was found in the Network Block Device(NBD) Server in all QEMU versions before QEMU 5.0.1. This flaw occurs when an nbd-client sends a spec-compliant request that is near the boundary of maximum permitted request length. A remote nbd-client could use this flaw to crash the qemu-nbd server resulting in a denial of service.

Affected products

Canonical Ubuntu Linux: 16.04, 18.04, 20.04
openSUSE Leap: 15.2
QEMU: before 5.0.1 — fixed in 5.0.1
Red Hat Enterprise Linux: 8.0

How to fix

Upgrade to a fixed version: QEMU 5.0.1. Check the vendor advisory for mitigations.

References

http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00086.html
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-10761
https://security.gentoo.org/glsa/202011-09
https://security.netapp.com/advisory/ntap-20200731-0001/
https://usn.ubuntu.com/4467-1/
https://www.openwall.com/lists/oss-security/2020/06/09/1
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00086.html
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-10761
https://security.gentoo.org/glsa/202011-09
https://security.netapp.com/advisory/ntap-20200731-0001/
https://usn.ubuntu.com/4467-1/
https://www.openwall.com/lists/oss-security/2020/06/09/1

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