CVE-2026-4437
gethostbyaddr and gethostbyaddr_r may incorrectly handle DNS response
- State
- Published
- Severity
- 7.5 High
- Published
- Mar 20, 2026
- Updated
- Oct 15, 2026
- Reserved
- Mar 19, 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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.5 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CISA-ADP |
Weaknesses
- CWE-125 Out-of-bounds read
Affected Products
| Product | Versions |
|---|---|
glibcThe GNU C Library |
|
References
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