UBUNTU-CVE-2021-3748

See a problem?
Please try reporting it to the source first.
Source
https://ubuntu.com/security/CVE-2021-3748
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3748.json
JSON Data
https://api.test.osv.dev/v1/vulns/UBUNTU-CVE-2021-3748
Upstream
Downstream
Related
Published
2021-08-31T00:00:00Z
Modified
2025-09-08T16:46:48Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

A use-after-free vulnerability was found in the virtio-net device of QEMU. It could occur when the descriptor's address belongs to the non direct access region, due to num_buffers being set after the virtqueue elem has been unmapped. A malicious guest could use this flaw to crash QEMU, resulting in a denial of service condition, or potentially execute code on the host with the privileges of the QEMU process.

References

Affected packages

Ubuntu:18.04:LTS / qemu

Package

Name
qemu
Purl
pkg:deb/ubuntu/qemu@1:2.11+dfsg-1ubuntu7.39?arch=source&distro=bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1:2.11+dfsg-1ubuntu7.39

Affected versions

1:2.*

1:2.10+dfsg-0ubuntu3
1:2.10+dfsg-0ubuntu4
1:2.10+dfsg-0ubuntu5
1:2.11+dfsg-1ubuntu1
1:2.11+dfsg-1ubuntu2
1:2.11+dfsg-1ubuntu4
1:2.11+dfsg-1ubuntu5
1:2.11+dfsg-1ubuntu6
1:2.11+dfsg-1ubuntu7
1:2.11+dfsg-1ubuntu7.1
1:2.11+dfsg-1ubuntu7.2
1:2.11+dfsg-1ubuntu7.3
1:2.11+dfsg-1ubuntu7.4
1:2.11+dfsg-1ubuntu7.5
1:2.11+dfsg-1ubuntu7.6
1:2.11+dfsg-1ubuntu7.7
1:2.11+dfsg-1ubuntu7.8
1:2.11+dfsg-1ubuntu7.9
1:2.11+dfsg-1ubuntu7.10
1:2.11+dfsg-1ubuntu7.12
1:2.11+dfsg-1ubuntu7.13
1:2.11+dfsg-1ubuntu7.14
1:2.11+dfsg-1ubuntu7.15
1:2.11+dfsg-1ubuntu7.17
1:2.11+dfsg-1ubuntu7.18
1:2.11+dfsg-1ubuntu7.19
1:2.11+dfsg-1ubuntu7.20
1:2.11+dfsg-1ubuntu7.21
1:2.11+dfsg-1ubuntu7.22
1:2.11+dfsg-1ubuntu7.23
1:2.11+dfsg-1ubuntu7.25
1:2.11+dfsg-1ubuntu7.26
1:2.11+dfsg-1ubuntu7.27
1:2.11+dfsg-1ubuntu7.28
1:2.11+dfsg-1ubuntu7.29
1:2.11+dfsg-1ubuntu7.31
1:2.11+dfsg-1ubuntu7.32
1:2.11+dfsg-1ubuntu7.33
1:2.11+dfsg-1ubuntu7.34
1:2.11+dfsg-1ubuntu7.35
1:2.11+dfsg-1ubuntu7.36
1:2.11+dfsg-1ubuntu7.37
1:2.11+dfsg-1ubuntu7.38

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "qemu",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-block-extra",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-guest-agent",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-kvm",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-system",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-system-arm",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-system-common",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-system-mips",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-system-misc",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-system-ppc",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-system-s390x",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-system-sparc",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-system-x86",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-user",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-user-binfmt",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-user-static",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        },
        {
            "binary_name": "qemu-utils",
            "binary_version": "1:2.11+dfsg-1ubuntu7.39"
        }
    ],
    "availability": "No subscription required"
}

Ubuntu:20.04:LTS / qemu

Package

Name
qemu
Purl
pkg:deb/ubuntu/qemu@1:4.2-3ubuntu6.21?arch=source&distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1:4.2-3ubuntu6.21

Affected versions

1:4.*

1:4.0+dfsg-0ubuntu9
1:4.0+dfsg-0ubuntu10
1:4.2-1ubuntu1
1:4.2-1ubuntu2
1:4.2-3ubuntu1
1:4.2-3ubuntu2
1:4.2-3ubuntu3
1:4.2-3ubuntu4
1:4.2-3ubuntu5
1:4.2-3ubuntu6
1:4.2-3ubuntu6.1
1:4.2-3ubuntu6.2
1:4.2-3ubuntu6.3
1:4.2-3ubuntu6.4
1:4.2-3ubuntu6.5
1:4.2-3ubuntu6.6
1:4.2-3ubuntu6.7
1:4.2-3ubuntu6.8
1:4.2-3ubuntu6.9
1:4.2-3ubuntu6.10
1:4.2-3ubuntu6.11
1:4.2-3ubuntu6.12
1:4.2-3ubuntu6.14
1:4.2-3ubuntu6.15
1:4.2-3ubuntu6.16
1:4.2-3ubuntu6.17
1:4.2-3ubuntu6.18
1:4.2-3ubuntu6.19

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "qemu",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-block-extra",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-guest-agent",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-kvm",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-arm",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-common",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-data",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-gui",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-mips",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-misc",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-ppc",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-s390x",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-sparc",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-x86",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-x86-microvm",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-system-x86-xen",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-user",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-user-binfmt",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-user-static",
            "binary_version": "1:4.2-3ubuntu6.21"
        },
        {
            "binary_name": "qemu-utils",
            "binary_version": "1:4.2-3ubuntu6.21"
        }
    ],
    "availability": "No subscription required"
}

Ubuntu:22.04:LTS / qemu

Package

Name
qemu
Purl
pkg:deb/ubuntu/qemu@1:6.2+dfsg-2ubuntu5?arch=source&distro=jammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1:6.2+dfsg-2ubuntu5

Affected versions

1:6.*

1:6.0+dfsg-2expubuntu1
1:6.0+dfsg-2expubuntu2
1:6.0+dfsg-2expubuntu4

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "qemu",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-block-extra",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-guest-agent",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-arm",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-common",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-data",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-gui",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-mips",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-misc",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-ppc",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-s390x",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-sparc",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-x86",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-x86-microvm",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-system-x86-xen",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-user",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-user-binfmt",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-user-static",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        },
        {
            "binary_name": "qemu-utils",
            "binary_version": "1:6.2+dfsg-2ubuntu5"
        }
    ],
    "availability": "No subscription required"
}