CVE-2026-4437
Published: March 24, 2026Last modified: April 2, 2026
Description
Calling gethostbyaddr or gethostbyaddr_r with a configured nsswitch.conf that specifies the library's DNS backend in the GNU C Library version 2.34 to version 2.43 could, with a crafted response from the configured DNS server, result in a violation of the DNS specification that causes the application to treat a non-answer section of the DNS response as a valid answer.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.5 |
| Attack Vector | NETWORK |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | glibc | Fixed (2.37.0-r22) |
| 25 LTS | glibc | Fixed (2.39.0-r7) | |
| Stream | glibc | Fixed (2.39.0-r8) | |
| Hardened Containers | 23 LTS | glibc | Fixed (2.37.0-r22) |
| 25 LTS | glibc | Fixed (2.39.0-r7) | |
| Stream | glibc | Fixed (2.39.0-r8) |