DEBIAN-CVE-2026-4437
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.
DEBIAN-CVE-2026-4437
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-4437
glibc
Source reference: /affected/0/package/name
- Affected versions
- 2.36-9
Source reference:
/affected/0/versions2.36-9+deb12u1Source reference:
/affected/0/versions2.36-9+deb12u10Source reference:
/affected/0/versions2.36-9+deb12u11Source reference:
/affected/0/versions2.36-9+deb12u12Source reference:
/affected/0/versions2.36-9+deb12u13Source reference:
/affected/0/versions2.36-9+deb12u2Source reference:
/affected/0/versions2.36-9+deb12u3Source reference:
/affected/0/versions2.36-9+deb12u4Source reference:
/affected/0/versions2.36-9+deb12u5Source reference:
/affected/0/versions2.36-9+deb12u6Source reference:
/affected/0/versions2.36-9+deb12u7Source reference:
/affected/0/versions2.36-9+deb12u8Source reference:
/affected/0/versions2.36-9+deb12u9Source reference:
/affected/0/versions - Fixed versions
- 2.36-9+deb12u14
Source reference:
/affected/0/ranges - Prerequisites
- Not stated in this record
glibc
Source reference: /affected/1/package/name
- Affected versions
- 2.41-12
Source reference:
/affected/1/versions2.41-12+deb13u1Source reference:
/affected/1/versions2.41-12+deb13u2Source reference:
/affected/1/versions - Fixed versions
- 2.41-12+deb13u3
Source reference:
/affected/1/ranges - Prerequisites
- Not stated in this record
glibc
Source reference: /affected/2/package/name
- Affected versions
- 2.41-12
Source reference:
/affected/2/versions2.41-13~hurd.0Source reference:
/affected/2/versions2.41-13~hurd.1Source reference:
/affected/2/versions2.42-1Source reference:
/affected/2/versions2.42-10Source reference:
/affected/2/versions2.42-11Source reference:
/affected/2/versions2.42-12Source reference:
/affected/2/versions2.42-12~hurd.1Source reference:
/affected/2/versions2.42-13Source reference:
/affected/2/versions2.42-14~hurd.1Source reference:
/affected/2/versions2.42-2Source reference:
/affected/2/versions2.42-3Source reference:
/affected/2/versions2.42-4Source reference:
/affected/2/versions2.42-5Source reference:
/affected/2/versions2.42-6Source reference:
/affected/2/versions2.42-7Source reference:
/affected/2/versions2.42-8Source reference:
/affected/2/versions2.42-8~hurd.1Source reference:
/affected/2/versions2.42-8~hurd.2Source reference:
/affected/2/versions2.42-9Source reference:
/affected/2/versions - Fixed versions
- 2.42-14
Source reference:
/affected/2/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.36-9+deb12u14"
}
]
}
],
"package": {
"name": "glibc",
"purl": "pkg:deb/debian/glibc?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"2.36-9",
"2.36-9+deb12u1",
"2.36-9+deb12u10",
"2.36-9+deb12u11",
"2.36-9+deb12u12",
"2.36-9+deb12u13",
"2.36-9+deb12u2",
"2.36-9+deb12u3",
"2.36-9+deb12u4",
"2.36-9+deb12u5",
"2.36-9+deb12u6",
"2.36-9+deb12u7",
"2.36-9+deb12u8",
"2.36-9+deb12u9"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-4437.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.41-12+deb13u3"
}
]
}
],
"package": {
"name": "glibc",
"purl": "pkg:deb/debian/glibc?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"2.41-12",
"2.41-12+deb13u1",
"2.41-12+deb13u2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-4437.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.42-14"
}
]
}
],
"package": {
"name": "glibc",
"purl": "pkg:deb/debian/glibc?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"2.41-12",
"2.41-13~hurd.0",
"2.41-13~hurd.1",
"2.42-1",
"2.42-10",
"2.42-11",
"2.42-12",
"2.42-12~hurd.1",
"2.42-13",
"2.42-14~hurd.1",
"2.42-2",
"2.42-3",
"2.42-4",
"2.42-5",
"2.42-6",
"2.42-7",
"2.42-8",
"2.42-8~hurd.1",
"2.42-8~hurd.2",
"2.42-9"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-4437.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #57685 · Revision 1
- Added to Heist Feed
- Publisher date