CVE-2026-4437

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Source
https://cve.org/CVERecord?id=CVE-2026-4437
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-4437.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-4437
Downstream
AZL (1)
BELL (1)
CGA (106)
CLSA (1)
DEBIAN (1)
ECHO (1)
MINI (3)
OESA (4)
openSUSE (2)
RHSA (3)
RLSA (2)
ROOT (4)
SUSE (6)
UBUNTU (1)
Related
ALSA (2)
CGA (1)
openSUSE (2)
SUSE (6)
Published
2026-03-20T19:59:00Z
Modified
2026-08-28T11:30:24Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
gethostbyaddr and gethostbyaddr_r may incorrectly handle DNS response
Details

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.

Database specific 
{
    "cna_assigner":  "glibc",
    "cwe_ids":  [
        "CWE-125"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/4xxx/CVE-2026-4437.json",
    "unresolved_ranges":  [
        {
            "extracted_events":  [
                {
                    "introduced":  "2.34"
                },
                {
                    "last_affected":  "2.43"
                }
            ],
            "source":  "AFFECTED_FIELD"
        }
    ]
}
References

Affected packages

Git / sourceware.org/git/glibc.git

Affected ranges

Type
GIT
Repo
https://sourceware.org/git/glibc.git
Events
Introduced
ae37d06c7d127817ba43850f0f898b793d42aea7
Last Affected
f762ccf84f122d1354f103a151cba8bde797d521
Database specific
Show details 
{
    "cpe":  "cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*",
    "extracted_events":  [
        {
            "introduced":  "2.34"
        },
        {
            "last_affected":  "2.43"
        }
    ],
    "source":  "CPE_RANGE"
}

Affected versions

glibc-2.*
glibc-2.34
glibc-2.34.9000
glibc-2.35
glibc-2.35.9000
glibc-2.36
glibc-2.36.9000
glibc-2.37
glibc-2.37.9000
glibc-2.38
glibc-2.38.9000
glibc-2.39
glibc-2.39.9000
glibc-2.40
glibc-2.40.9000
glibc-2.41
glibc-2.41.9000
glibc-2.42
glibc-2.42.9000
glibc-2.43

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-4437.json"