CVE-2026-18664
When ranges are used for access control (i.e. of the form 1.2.3.4-1.2. ...
Severity by source
Trivy's own label is CRITICAL. Rated critical by NVD.
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.
Affected packages and fixed versions
| Source | Package | Fixed in |
|---|---|---|
| alpine edge | nsd | 4.15.1-r0 |
| debian 11 | nsd | no fix listed |
| debian 12 | nsd | no fix listed |
| debian 13 | nsd | no fix listed |
| debian 14 | nsd | 4.15.1-1 |
| echo | nsd | no fix listed |
| rapidfort alpine 3.20 | nsd | 4.15.1-r0 |
| rapidfort alpine 3.21 | nsd | 4.15.1-r0 |
| rapidfort alpine 3.22 | nsd | 4.15.1-r0 |
| rapidfort alpine 3.23 | nsd | 4.15.1-r0 |
| rapidfort alpine 3.24 | nsd | 4.15.1-r0 |
| rapidfort debian 12 | nsd | 0:4.15.1-1 |
Show all 19 entries from 19 sources
| Source | Package | Fixed in |
|---|---|---|
| alpine edge | nsd | 4.15.1-r0 |
| debian 11 | nsd | no fix listed |
| debian 12 | nsd | no fix listed |
| debian 13 | nsd | no fix listed |
| debian 14 | nsd | 4.15.1-1 |
| echo | nsd | no fix listed |
| rapidfort alpine 3.20 | nsd | 4.15.1-r0 |
| rapidfort alpine 3.21 | nsd | 4.15.1-r0 |
| rapidfort alpine 3.22 | nsd | 4.15.1-r0 |
| rapidfort alpine 3.23 | nsd | 4.15.1-r0 |
| rapidfort alpine 3.24 | nsd | 4.15.1-r0 |
| rapidfort debian 12 | nsd | 0:4.15.1-1 |
| rapidfort debian 13 | nsd | 0:4.15.1-1 |
| rapidfort fedora 43 | nsd | 4.15.1-1.fc43 |
| rapidfort Oracle Linux 10 | nsd | 4.15.1-1.el10_4 |
| rapidfort Oracle Linux 9 | nsd | 4.15.1-1.el9 |
| rapidfort ubuntu 20.04 | nsd | no fix listed |
| rapidfort ubuntu 22.04 | nsd | no fix listed |
| rapidfort ubuntu 24.04 | nsd | no fix listed |