UBUNTU-CVE-2026-40211

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Source
https://ubuntu.com/security/CVE-2026-40211
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40211.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-40211
Upstream
  • CVE-2026-40211
Published
2026-06-25T13:16:00Z
Modified
2026-06-29T23:15:39.228814894Z
Severity
  • 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

An attacker can send crafted DNS over HTTP/3 queries, triggering an exception that prevents some buffer from being freed right away. The buffer will be freed at the end of the QUIC connection, but on some setups it might be possible to open enough concurrent DoH3 streams to trigger an out-of-memory condition, resulting in a denial of service.

References

Affected packages

Ubuntu:16.04:LTS
dnsdist

Package

Name
dnsdist
Purl
pkg:deb/ubuntu/dnsdist?arch=source&distro=xenial

Affected ranges

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

Affected versions

1.*
1.0.0~alpha2-1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "dnsdist",
            "binary_version": "1.0.0~alpha2-1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40211.json"
Ubuntu:25.10
dnsdist

Package

Name
dnsdist
Purl
pkg:deb/ubuntu/dnsdist?arch=source&distro=questing

Affected ranges

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

Affected versions

1.*
1.9.8-1
1.9.10-1
1.9.10-1ubuntu0.1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "dnsdist",
            "binary_version": "1.9.10-1ubuntu0.1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40211.json"
Ubuntu:26.04:LTS
dnsdist

Package

Name
dnsdist
Purl
pkg:deb/ubuntu/dnsdist?arch=source&distro=resolute

Affected ranges

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

Affected versions

1.*
1.9.10-1
2.*
2.0.1-1
2.0.2-1
2.0.2-1build1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "dnsdist",
            "binary_version": "2.0.2-1build1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40211.json"
Ubuntu:Pro:18.04:LTS
dnsdist

Package

Name
dnsdist
Purl
pkg:deb/ubuntu/dnsdist?arch=source&distro=esm-apps%2Fbionic

Affected ranges

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

Affected versions

1.*
1.2.0-1
1.2.0-3
1.2.1-1
1.2.1-1build1
1.2.1-1ubuntu0.1~esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "dnsdist",
            "binary_version": "1.2.1-1ubuntu0.1~esm1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40211.json"
Ubuntu:Pro:20.04:LTS
dnsdist

Package

Name
dnsdist
Purl
pkg:deb/ubuntu/dnsdist?arch=source&distro=esm-apps%2Ffocal

Affected ranges

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

Affected versions

1.*
1.4.0~rc3-1
1.4.0-1
1.4.0-1build1
1.4.0-1build2
1.4.0-1ubuntu0.1~esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "dnsdist",
            "binary_version": "1.4.0-1ubuntu0.1~esm1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40211.json"
Ubuntu:Pro:22.04:LTS
dnsdist

Package

Name
dnsdist
Purl
pkg:deb/ubuntu/dnsdist?arch=source&distro=esm-apps%2Fjammy

Affected ranges

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

Affected versions

1.*
1.5.1-3build2
1.6.1-1build1
1.6.1-1ubuntu0.1~esm1
1.6.1-1ubuntu0.1~esm2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "dnsdist",
            "binary_version": "1.6.1-1ubuntu0.1~esm2"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40211.json"
Ubuntu:Pro:24.04:LTS
dnsdist

Package

Name
dnsdist
Purl
pkg:deb/ubuntu/dnsdist?arch=source&distro=esm-apps%2Fnoble

Affected ranges

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

Affected versions

1.*
1.8.0-1
1.8.2-1
1.8.2-2
1.8.2-3
1.8.3-1
1.8.3-2
1.8.3-2build1
1.8.3-2build2
1.8.3-2ubuntu0.1~esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "dnsdist",
            "binary_version": "1.8.3-2ubuntu0.1~esm1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40211.json"