CVE-2026-18664

Name
CVE-2026-18664
Description
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.
NVD Severity
unknown
Other trackers
Mailing lists
Exploits
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
sep@nlnetlabs.nl https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-18664.txt

Match rules

CPE URI Source package Min version Max version
cpe:2.3:a:nlnetlabs:nsd:*:*:*:*:*:*:*:* nsd >= 3.0.0 < 4.15.1

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
nsd edge-main 4.15.1-r0 Natanael Copa <ncopa@alpinelinux.org> fixed
nsd edge-main 4.15.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.14.3-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.14.2-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.14.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.14.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.13.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.12.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.11.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.11.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.10.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd edge-main 4.3.4-r0 None possibly vulnerable
nsd 3.24-main 4.14.3-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.24-main 4.14.2-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.23-main 4.13.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.22-main 4.12.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.22-main 4.3.4-r0 None possibly vulnerable
nsd 3.21-main 4.11.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.21-main 4.11.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.21-main 4.10.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.21-main 4.3.4-r0 None possibly vulnerable
nsd 3.20-main 4.9.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.20-main 4.3.4-r0 None possibly vulnerable
nsd 3.19-main 4.7.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
nsd 3.19-main 4.3.4-r0 None possibly vulnerable