CVE-2026-4437
High
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.
SeverityHigh
CVSS7.5
Exploit probability—
Product
Gnu Glibc
PublishedMar 20, 2026
First seenMar 20, 2026
Weakness typeCWE-125Out-of-bounds read
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| gnu glibc | 2.34 ≤ v ≤ 2.43 | — |
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