UBUNTU-CVE-2025-5994

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Source
https://ubuntu.com/security/CVE-2025-5994
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-5994.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2025-5994
Upstream
Downstream
Related
Published
2025-07-17T00:00:00Z
Modified
2025-10-24T05:16:33Z
Severity
  • 8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/R:U/V:C CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

A multi-vendor cache poisoning vulnerability named 'Rebirthday Attack' has been discovered in caching resolvers that support EDNS Client Subnet (ECS). Unbound is also vulnerable when compiled with ECS support, i.e., '--enable-subnet', AND configured to send ECS information along with queries to upstream name servers, i.e., at least one of the 'send-client-subnet', 'client-subnet-zone' or 'client-subnet-always-forward' options is used. Resolvers supporting ECS need to segregate outgoing queries to accommodate for different outgoing ECS information. This re-opens up resolvers to a birthday paradox attack (Rebirthday Attack) that tries to match the DNS transaction ID in order to cache non-ECS poisonous replies.

References

Affected packages

Ubuntu:20.04:LTS

unbound

Package

Name
unbound
Purl
pkg:deb/ubuntu/unbound@1.9.4-2ubuntu1.11?arch=source&distro=focal

Affected ranges

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

Affected versions

1.*

1.9.0-2ubuntu1
1.9.0-2ubuntu2
1.9.4-2
1.9.4-2ubuntu1
1.9.4-2ubuntu1.1
1.9.4-2ubuntu1.2
1.9.4-2ubuntu1.3
1.9.4-2ubuntu1.4
1.9.4-2ubuntu1.5
1.9.4-2ubuntu1.6
1.9.4-2ubuntu1.8
1.9.4-2ubuntu1.9
1.9.4-2ubuntu1.11

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libunbound-dev",
            "binary_version": "1.9.4-2ubuntu1.11"
        },
        {
            "binary_name": "libunbound8",
            "binary_version": "1.9.4-2ubuntu1.11"
        },
        {
            "binary_name": "python-unbound",
            "binary_version": "1.9.4-2ubuntu1.11"
        },
        {
            "binary_name": "python3-unbound",
            "binary_version": "1.9.4-2ubuntu1.11"
        },
        {
            "binary_name": "unbound",
            "binary_version": "1.9.4-2ubuntu1.11"
        },
        {
            "binary_name": "unbound-anchor",
            "binary_version": "1.9.4-2ubuntu1.11"
        },
        {
            "binary_name": "unbound-host",
            "binary_version": "1.9.4-2ubuntu1.11"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-5994.json"

Ubuntu:22.04:LTS

unbound

Package

Name
unbound
Purl
pkg:deb/ubuntu/unbound@1.13.1-1ubuntu5.11?arch=source&distro=jammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.13.1-1ubuntu5.11

Affected versions

1.*

1.13.1-1ubuntu1
1.13.1-1ubuntu3
1.13.1-1ubuntu5
1.13.1-1ubuntu5.1
1.13.1-1ubuntu5.2
1.13.1-1ubuntu5.3
1.13.1-1ubuntu5.4
1.13.1-1ubuntu5.5
1.13.1-1ubuntu5.7
1.13.1-1ubuntu5.8
1.13.1-1ubuntu5.10

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libunbound-dev",
            "binary_version": "1.13.1-1ubuntu5.11"
        },
        {
            "binary_name": "libunbound8",
            "binary_version": "1.13.1-1ubuntu5.11"
        },
        {
            "binary_name": "python3-unbound",
            "binary_version": "1.13.1-1ubuntu5.11"
        },
        {
            "binary_name": "unbound",
            "binary_version": "1.13.1-1ubuntu5.11"
        },
        {
            "binary_name": "unbound-anchor",
            "binary_version": "1.13.1-1ubuntu5.11"
        },
        {
            "binary_name": "unbound-host",
            "binary_version": "1.13.1-1ubuntu5.11"
        }
    ],
    "availability": "No subscription required"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-5994.json"

Ubuntu:24.04:LTS

unbound

Package

Name
unbound
Purl
pkg:deb/ubuntu/unbound@1.19.2-1ubuntu3.5?arch=source&distro=noble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.19.2-1ubuntu3.5

Affected versions

1.*

1.17.1-2
1.18.0-2ubuntu1
1.18.0-2ubuntu2
1.19.1-1ubuntu1
1.19.2-1ubuntu1
1.19.2-1ubuntu3
1.19.2-1ubuntu3.1
1.19.2-1ubuntu3.2
1.19.2-1ubuntu3.3
1.19.2-1ubuntu3.4

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libunbound-dev",
            "binary_version": "1.19.2-1ubuntu3.5"
        },
        {
            "binary_name": "libunbound8",
            "binary_version": "1.19.2-1ubuntu3.5"
        },
        {
            "binary_name": "python3-unbound",
            "binary_version": "1.19.2-1ubuntu3.5"
        },
        {
            "binary_name": "unbound",
            "binary_version": "1.19.2-1ubuntu3.5"
        },
        {
            "binary_name": "unbound-anchor",
            "binary_version": "1.19.2-1ubuntu3.5"
        },
        {
            "binary_name": "unbound-host",
            "binary_version": "1.19.2-1ubuntu3.5"
        }
    ],
    "availability": "No subscription required"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-5994.json"

Ubuntu:25.04

unbound

Package

Name
unbound
Purl
pkg:deb/ubuntu/unbound@1.22.0-1ubuntu1.1?arch=source&distro=plucky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.22.0-1ubuntu1.1

Affected versions

1.*

1.20.0-1ubuntu2
1.20.0-1ubuntu2.1
1.20.0-1ubuntu2.2
1.22.0-1ubuntu1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libunbound-dev",
            "binary_version": "1.22.0-1ubuntu1.1"
        },
        {
            "binary_name": "libunbound8",
            "binary_version": "1.22.0-1ubuntu1.1"
        },
        {
            "binary_name": "python3-unbound",
            "binary_version": "1.22.0-1ubuntu1.1"
        },
        {
            "binary_name": "unbound",
            "binary_version": "1.22.0-1ubuntu1.1"
        },
        {
            "binary_name": "unbound-anchor",
            "binary_version": "1.22.0-1ubuntu1.1"
        },
        {
            "binary_name": "unbound-host",
            "binary_version": "1.22.0-1ubuntu1.1"
        }
    ],
    "availability": "No subscription required"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-5994.json"

Ubuntu:25.10

unbound

Package

Name
unbound
Purl
pkg:deb/ubuntu/unbound@1.22.0-2ubuntu1?arch=source&distro=questing

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.22.0-2ubuntu1

Affected versions

1.*

1.22.0-1ubuntu1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libunbound-dev",
            "binary_version": "1.22.0-2ubuntu1"
        },
        {
            "binary_name": "libunbound8",
            "binary_version": "1.22.0-2ubuntu1"
        },
        {
            "binary_name": "python3-unbound",
            "binary_version": "1.22.0-2ubuntu1"
        },
        {
            "binary_name": "unbound",
            "binary_version": "1.22.0-2ubuntu1"
        },
        {
            "binary_name": "unbound-anchor",
            "binary_version": "1.22.0-2ubuntu1"
        },
        {
            "binary_name": "unbound-host",
            "binary_version": "1.22.0-2ubuntu1"
        }
    ],
    "availability": "No subscription required"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-5994.json"

Ubuntu:Pro:14.04:LTS

unbound

Package

Name
unbound
Purl
pkg:deb/ubuntu/unbound@1.4.22-1ubuntu4.14.04.3+esm2?arch=source&distro=esm-infra-legacy/trusty

Affected ranges

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

Affected versions

1.*

1.4.20-1
1.4.21-1
1.4.21-1ubuntu1
1.4.21-1ubuntu2
1.4.22-1ubuntu1
1.4.22-1ubuntu2
1.4.22-1ubuntu3
1.4.22-1ubuntu4
1.4.22-1ubuntu4.14.04.1
1.4.22-1ubuntu4.14.04.2
1.4.22-1ubuntu4.14.04.3
1.4.22-1ubuntu4.14.04.3+esm1
1.4.22-1ubuntu4.14.04.3+esm2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libunbound-dev",
            "binary_version": "1.4.22-1ubuntu4.14.04.3+esm2"
        },
        {
            "binary_name": "libunbound2",
            "binary_version": "1.4.22-1ubuntu4.14.04.3+esm2"
        },
        {
            "binary_name": "python-unbound",
            "binary_version": "1.4.22-1ubuntu4.14.04.3+esm2"
        },
        {
            "binary_name": "unbound",
            "binary_version": "1.4.22-1ubuntu4.14.04.3+esm2"
        },
        {
            "binary_name": "unbound-anchor",
            "binary_version": "1.4.22-1ubuntu4.14.04.3+esm2"
        },
        {
            "binary_name": "unbound-host",
            "binary_version": "1.4.22-1ubuntu4.14.04.3+esm2"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-5994.json"

Ubuntu:Pro:16.04:LTS

unbound

Package

Name
unbound
Purl
pkg:deb/ubuntu/unbound@1.5.8-1ubuntu1.1+esm2?arch=source&distro=esm-infra/xenial

Affected ranges

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

Affected versions

1.*

1.4.22-1ubuntu6
1.5.7-1ubuntu1
1.5.7-1ubuntu2
1.5.8-1ubuntu1
1.5.8-1ubuntu1.1
1.5.8-1ubuntu1.1+esm1
1.5.8-1ubuntu1.1+esm2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libunbound-dev",
            "binary_version": "1.5.8-1ubuntu1.1+esm2"
        },
        {
            "binary_name": "libunbound2",
            "binary_version": "1.5.8-1ubuntu1.1+esm2"
        },
        {
            "binary_name": "python-unbound",
            "binary_version": "1.5.8-1ubuntu1.1+esm2"
        },
        {
            "binary_name": "unbound",
            "binary_version": "1.5.8-1ubuntu1.1+esm2"
        },
        {
            "binary_name": "unbound-anchor",
            "binary_version": "1.5.8-1ubuntu1.1+esm2"
        },
        {
            "binary_name": "unbound-host",
            "binary_version": "1.5.8-1ubuntu1.1+esm2"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-5994.json"

Ubuntu:Pro:18.04:LTS

unbound

Package

Name
unbound
Purl
pkg:deb/ubuntu/unbound@1.6.7-1ubuntu2.6+esm3?arch=source&distro=esm-infra/bionic

Affected ranges

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

Affected versions

1.*

1.6.5-1
1.6.7-1
1.6.7-1build1
1.6.7-1ubuntu1
1.6.7-1ubuntu2
1.6.7-1ubuntu2.1
1.6.7-1ubuntu2.2
1.6.7-1ubuntu2.3
1.6.7-1ubuntu2.4
1.6.7-1ubuntu2.5
1.6.7-1ubuntu2.6
1.6.7-1ubuntu2.6+esm2
1.6.7-1ubuntu2.6+esm3

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libunbound-dev",
            "binary_version": "1.6.7-1ubuntu2.6+esm3"
        },
        {
            "binary_name": "libunbound2",
            "binary_version": "1.6.7-1ubuntu2.6+esm3"
        },
        {
            "binary_name": "python-unbound",
            "binary_version": "1.6.7-1ubuntu2.6+esm3"
        },
        {
            "binary_name": "python3-unbound",
            "binary_version": "1.6.7-1ubuntu2.6+esm3"
        },
        {
            "binary_name": "unbound",
            "binary_version": "1.6.7-1ubuntu2.6+esm3"
        },
        {
            "binary_name": "unbound-anchor",
            "binary_version": "1.6.7-1ubuntu2.6+esm3"
        },
        {
            "binary_name": "unbound-host",
            "binary_version": "1.6.7-1ubuntu2.6+esm3"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-5994.json"