UBUNTU-CVE-2026-42944
- Source
- https://ubuntu.com/security/CVE-2026-42944
- Import Source
- https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-42944.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/UBUNTU-CVE-2026-42944
- Upstream
- Downstream
- Related
- Published
- 2026-05-20T00:00:00Z
- Modified
- 2026-06-01T20:30:06.104720760Z
- Severity
-
- 8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/U:Red 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
-
NLnet Labs Unbound 1.14.0 up to and including version 1.25.0 has a vulnerability that results in heap overflow when encoding multiple NSID and/or DNS Cookie EDNS and/or EDNS Padding options in the reply packet. The relevant options ('nsid', 'answer-cookie', 'pad-responses' (default)) need to be enabled for the vulnerability to be exploited. An adversary who can query Unbound can exploit the vulnerability by attaching multiple NSID and/or DNS Cookie EDNS and/or EDNS Padding options to the query. A flaw in the size calculation of the EDNS field truncates the correct value which allows the encoder to overflow the available space when writing. Those two combined lead to a heap overflow write of Unbound controlled data and eventually a crash. Unbound 1.25.1 contains a patch with a fix to de-duplicate the EDNS options and a fix to prevent truncation of the EDNS field size calculation.
- References
Affected packages
Ubuntu:24.04:LTS / unbound
Package
- Name
- unbound
- Purl
- pkg:deb/ubuntu/unbound?arch=source&distro=noble
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affectedFixed1.19.2-1ubuntu3.8
Affected versions
1.*
Ecosystem specific
{
"availability": "No subscription required",
"binaries": [
{
"binary_version": "1.19.2-1ubuntu3.8",
"binary_name": "libunbound8"
},
{
"binary_name": "python3-unbound",
"binary_version": "1.19.2-1ubuntu3.8"
},
{
"binary_name": "unbound",
"binary_version": "1.19.2-1ubuntu3.8"
},
{
"binary_name": "unbound-anchor",
"binary_version": "1.19.2-1ubuntu3.8"
},
{
"binary_name": "unbound-host",
"binary_version": "1.19.2-1ubuntu3.8"
}
]
}
Ubuntu:25.10 / unbound
Package
- Name
- unbound
- Purl
- pkg:deb/ubuntu/unbound?arch=source&distro=questing
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affectedFixed1.22.0-2ubuntu2.3
Affected versions
1.*
Ecosystem specific
{
"availability": "No subscription required",
"binaries": [
{
"binary_version": "1.22.0-2ubuntu2.3",
"binary_name": "libunbound8"
},
{
"binary_name": "python3-unbound",
"binary_version": "1.22.0-2ubuntu2.3"
},
{
"binary_version": "1.22.0-2ubuntu2.3",
"binary_name": "unbound"
},
{
"binary_version": "1.22.0-2ubuntu2.3",
"binary_name": "unbound-anchor"
},
{
"binary_name": "unbound-host",
"binary_version": "1.22.0-2ubuntu2.3"
}
]
}
Ubuntu:26.04:LTS / unbound
Package
- Name
- unbound
- Purl
- pkg:deb/ubuntu/unbound?arch=source&distro=resolute
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affectedFixed1.24.2-1ubuntu2.1
Ecosystem specific
{
"availability": "No subscription required",
"binaries": [
{
"binary_name": "libunbound8",
"binary_version": "1.24.2-1ubuntu2.1"
},
{
"binary_version": "1.24.2-1ubuntu2.1",
"binary_name": "python3-unbound"
},
{
"binary_name": "unbound",
"binary_version": "1.24.2-1ubuntu2.1"
},
{
"binary_name": "unbound-anchor",
"binary_version": "1.24.2-1ubuntu2.1"
},
{
"binary_name": "unbound-host",
"binary_version": "1.24.2-1ubuntu2.1"
}
]
}