CVE-2025-40776
Publication date 16 July 2025
Last updated 23 July 2025
Ubuntu priority
A `named` caching resolver that is configured to send ECS (EDNS Client Subnet) options may be vulnerable to a cache-poisoning attack. This issue affects BIND 9 versions 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.37-S1, and 9.20.9-S1 through 9.20.10-S1.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| bind9 | 25.04 plucky |
Not affected
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
|
| 20.04 LTS focal |
Not affected
|
|
| 18.04 LTS bionic |
Not affected
|
|
| 16.04 LTS xenial |
Not affected
|
|
| 14.04 LTS trusty |
Not affected
|
|
| isc-dhcp | 25.04 plucky |
Not affected
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
|
| 20.04 LTS focal |
Not affected
|
|
| 18.04 LTS bionic |
Not affected
|
|
| 16.04 LTS xenial |
Not affected
|
|
| 14.04 LTS trusty |
Not affected
|
|
| bind9-libs | 25.04 plucky | Not in release |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy |
Not affected
|
|
| 20.04 LTS focal |
Not affected
|
Notes
alexmurray
As of isc-dhcp-4.4.3-1, isc-dhcp vendors bind9 libs
mdeslaur
in focal and jammy, isc-dhcp uses the bind9-libs package
rodrigo-zaiden
affects subscription edition (-S) versions of bind9
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
8.6 · High
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Changed |
| Confidentiality | None |
| Integrity impact | High |
| Availability impact | None |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N |