DEBIAN-CVE-2026-18664
When ranges are used for access control (i.e. of the form 1.2.3.4-1.2.3.25), because NSD wrongly compares the IP address with the range on little endian systems, IPs that were meant to be allowed may be denied, and, IPs that were meant to be denied access could be allowed. An IPv4 address is compared with IPv4 ranges as unsigned 32 bit numbers directly with the endianness of the host, but the values to compare are in network byte order (big-endian). With IPv6 addresses the comparison is done in 4 times a unsigned 32 bit number comparison, again with the endianness of the host where all values are actually in network bye order.
DEBIAN-CVE-2026-18664
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-18664
nsd
Source reference: /affected/0/package/name
- Affected versions
- 4.10.1-1
Source reference:
/affected/0/versions4.10.1~rc2-1Source reference:
/affected/0/versions4.10.1~rc2-2Source reference:
/affected/0/versions4.11.0-1Source reference:
/affected/0/versions4.11.1-1Source reference:
/affected/0/versions4.12.0-1Source reference:
/affected/0/versions4.12.0-2Source reference:
/affected/0/versions4.13.0-1Source reference:
/affected/0/versions4.13.0-2Source reference:
/affected/0/versions4.13.0-3Source reference:
/affected/0/versions4.13.0-4Source reference:
/affected/0/versions4.13.0-5Source reference:
/affected/0/versions4.13.0-6Source reference:
/affected/0/versions4.14.0-1Source reference:
/affected/0/versions4.14.1-1Source reference:
/affected/0/versions4.14.2-1Source reference:
/affected/0/versions4.14.3-1Source reference:
/affected/0/versions4.15.0-1Source reference:
/affected/0/versions4.15.0~rc1-1Source reference:
/affected/0/versions4.15.1-1Source reference:
/affected/0/versions4.15.2-1Source reference:
/affected/0/versions4.6.1-1Source reference:
/affected/0/versions4.7.0-1Source reference:
/affected/0/versions4.8.0-1Source reference:
/affected/0/versions4.9.1-1Source reference:
/affected/0/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
nsd
Source reference: /affected/1/package/name
- Affected versions
- 4.12.0-1
Source reference:
/affected/1/versions4.12.0-2Source reference:
/affected/1/versions4.13.0-1Source reference:
/affected/1/versions4.13.0-2Source reference:
/affected/1/versions4.13.0-3Source reference:
/affected/1/versions4.13.0-4Source reference:
/affected/1/versions4.13.0-5Source reference:
/affected/1/versions4.13.0-6Source reference:
/affected/1/versions4.14.0-1Source reference:
/affected/1/versions4.14.1-1Source reference:
/affected/1/versions4.14.2-1Source reference:
/affected/1/versions4.14.3-1Source reference:
/affected/1/versions4.15.0-1Source reference:
/affected/1/versions4.15.0~rc1-1Source reference:
/affected/1/versions4.15.1-1Source reference:
/affected/1/versions4.15.2-1Source reference:
/affected/1/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
nsd
Source reference: /affected/2/package/name
- Affected versions
- 4.12.0-1
Source reference:
/affected/2/versions4.12.0-2Source reference:
/affected/2/versions4.13.0-1Source reference:
/affected/2/versions4.13.0-2Source reference:
/affected/2/versions4.13.0-3Source reference:
/affected/2/versions4.13.0-4Source reference:
/affected/2/versions4.13.0-5Source reference:
/affected/2/versions4.13.0-6Source reference:
/affected/2/versions4.14.0-1Source reference:
/affected/2/versions4.14.1-1Source reference:
/affected/2/versions4.14.2-1Source reference:
/affected/2/versions4.14.3-1Source reference:
/affected/2/versions4.15.0-1Source reference:
/affected/2/versions4.15.0~rc1-1Source reference:
/affected/2/versions - Fixed versions
- 4.15.1-1
Source reference:
/affected/2/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "nsd",
"purl": "pkg:deb/debian/nsd?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"4.10.1-1",
"4.10.1~rc2-1",
"4.10.1~rc2-2",
"4.11.0-1",
"4.11.1-1",
"4.12.0-1",
"4.12.0-2",
"4.13.0-1",
"4.13.0-2",
"4.13.0-3",
"4.13.0-4",
"4.13.0-5",
"4.13.0-6",
"4.14.0-1",
"4.14.1-1",
"4.14.2-1",
"4.14.3-1",
"4.15.0-1",
"4.15.0~rc1-1",
"4.15.1-1",
"4.15.2-1",
"4.6.1-1",
"4.7.0-1",
"4.8.0-1",
"4.9.1-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-18664.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "nsd",
"purl": "pkg:deb/debian/nsd?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"4.12.0-1",
"4.12.0-2",
"4.13.0-1",
"4.13.0-2",
"4.13.0-3",
"4.13.0-4",
"4.13.0-5",
"4.13.0-6",
"4.14.0-1",
"4.14.1-1",
"4.14.2-1",
"4.14.3-1",
"4.15.0-1",
"4.15.0~rc1-1",
"4.15.1-1",
"4.15.2-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-18664.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.15.1-1"
}
]
}
],
"package": {
"name": "nsd",
"purl": "pkg:deb/debian/nsd?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"4.12.0-1",
"4.12.0-2",
"4.13.0-1",
"4.13.0-2",
"4.13.0-3",
"4.13.0-4",
"4.13.0-5",
"4.13.0-6",
"4.14.0-1",
"4.14.1-1",
"4.14.2-1",
"4.14.3-1",
"4.15.0-1",
"4.15.0~rc1-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-18664.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #56169 · Revision 1
- Added to Heist Feed
- Publisher date