UBUNTU-CVE-2023-26249

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Source
https://ubuntu.com/security/CVE-2023-26249
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-26249.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2023-26249
Upstream
Published
2023-02-21T02:15:00Z
Modified
2025-09-08T16:56:10Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

Knot Resolver before 5.6.0 enables attackers to consume its resources, launching amplification attacks and potentially causing a denial of service. Specifically, a single client query may lead to a hundred TCP connection attempts if a DNS server closes connections without providing a response.

References

Affected packages

Ubuntu:Pro:16.04:LTS / knot-resolver

Package

Name
knot-resolver
Purl
pkg:deb/ubuntu/knot-resolver@1.0.0~beta3-1ubuntu0.1~esm1?arch=source&distro=esm-apps/xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.0.0~beta2-123-g6134920-1
1.0.0~beta3-1
1.0.0~beta3-1ubuntu0.1~esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_version": "1.0.0~beta3-1ubuntu0.1~esm1",
            "binary_name": "knot-resolver"
        }
    ]
}

Ubuntu:Pro:18.04:LTS / knot-resolver

Package

Name
knot-resolver
Purl
pkg:deb/ubuntu/knot-resolver@2.1.1-1ubuntu0.1~esm2?arch=source&distro=esm-apps/bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.3.3-1
1.5.0-4
1.5.1-1
1.5.2-1

2.*

2.0.0-3
2.1.0-1
2.1.0-2
2.1.1-1
2.1.1-1ubuntu0.1~esm2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_version": "2.1.1-1ubuntu0.1~esm2",
            "binary_name": "knot-resolver"
        },
        {
            "binary_version": "2.1.1-1ubuntu0.1~esm2",
            "binary_name": "knot-resolver-module-http"
        },
        {
            "binary_version": "2.1.1-1ubuntu0.1~esm2",
            "binary_name": "libkres-dev"
        },
        {
            "binary_version": "2.1.1-1ubuntu0.1~esm2",
            "binary_name": "libkres6"
        }
    ]
}

Ubuntu:Pro:20.04:LTS / knot-resolver

Package

Name
knot-resolver
Purl
pkg:deb/ubuntu/knot-resolver@3.2.1-3ubuntu2.2?arch=source&distro=esm-apps/focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

3.*

3.2.1-3
3.2.1-3ubuntu1
3.2.1-3ubuntu2
3.2.1-3ubuntu2.1
3.2.1-3ubuntu2.2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_version": "3.2.1-3ubuntu2.2",
            "binary_name": "knot-resolver"
        },
        {
            "binary_version": "3.2.1-3ubuntu2.2",
            "binary_name": "knot-resolver-module-http"
        }
    ]
}

Ubuntu:22.04:LTS / knot-resolver

Package

Name
knot-resolver
Purl
pkg:deb/ubuntu/knot-resolver@5.4.4-1?arch=source&distro=jammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

5.*

5.3.1-1
5.4.2-1
5.4.3-1
5.4.4-1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_version": "5.4.4-1",
            "binary_name": "knot-resolver"
        },
        {
            "binary_version": "5.4.4-1",
            "binary_name": "knot-resolver-module-http"
        }
    ]
}