CVE catalog

CVE-2019-16866

Unbound before 1.9.4 accesses uninitialized memory, which allows remote attackers to trigger a crash via a crafted NOTIFY query. The source IP address of the query must match an access-control rule.

[CVE catalog]

Severity: High · CVSS 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: Oct 3, 2019, 12:00:00 AM UTC
Updated: Oct 8, 2026, 9:17:16 PM UTC
Source: [NVD] · [CVE record]
EPSS: 3.51% · Oct 25, 2026

Unbound before 1.9.4 accesses uninitialized memory, which allows remote attackers to trigger a crash via a crafted NOTIFY query. The source IP address of the query must match an access-control rule.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	unbound	sid	`1.26.2-1`	fixed
Debian	unbound	forky	`1.26.2-1`	fixed
Debian	unbound	trixie	`1.22.0-2+deb13u3`	fixed
Debian	unbound	trixie-security	`1.26.2-0+deb13u1`	fixed
Debian	unbound	bookworm	`1.17.1-2+deb12u4`	fixed
Debian	unbound	bookworm-security	`1.17.1-2+deb12u3`	fixed
Cpe	unbound	Not reported	`1.9.4`	fixed
Cpe	ubuntu_linux	Not reported	Not reported	unknown
Alpine	unbound	3.10	`1.9.1-r3`	fixed
Alpine	unbound	3.11	`1.9.4-r0`	fixed
Alpine	unbound	3.12	`1.9.4-r0`	fixed
Alpine	unbound	3.13	`1.9.4-r0`	fixed
Alpine	unbound	3.14	`1.9.4-r0`	fixed
Alpine	unbound	3.15	`1.9.4-r0`	fixed
Alpine	unbound	3.16	`1.9.4-r0`	fixed
Alpine	unbound	3.17	`1.9.4-r0`	fixed
Alpine	unbound	3.18	`1.9.4-r0`	fixed
Alpine	unbound	3.19	`1.9.4-r0`	fixed
Alpine	unbound	3.20	`1.9.4-r0`	fixed
Alpine	unbound	3.21	`1.9.4-r0`	fixed
Alpine	unbound	3.22	`1.9.4-r0`	fixed
Alpine	unbound	3.23	`1.9.4-r0`	fixed
Alpine	unbound	3.24	`1.9.4-r0`	fixed
Alpine	unbound	3.8	`1.7.3-r1`	fixed
Alpine	unbound	3.9	`1.8.3-r2`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	unbound	source	sid	`1.9.4-1`	not yet assigned	Not reported	[941692]
Debian	unbound	source	forky	`1.9.4-1`	not yet assigned	Not reported	[941692]
Debian	unbound	source	trixie	`1.9.4-1`	not yet assigned	Not reported	[941692]
Debian	unbound	source	bookworm	`1.9.4-1`	not yet assigned	Not reported	[941692]
Cpe	unbound	cpe	Not reported	`1.9.4`	Not reported	NVD-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.10	`1.9.1-r3`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.11	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.12	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.13	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.14	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.15	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.16	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.17	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.18	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.19	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.20	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.21	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.22	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.23	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.24	`1.9.4-r0`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.8	`1.7.3-r1`	Not reported	ALPINE-CVE-2019-16866	Not reported
Alpine	unbound	apk	3.9	`1.8.3-r2`	Not reported	ALPINE-CVE-2019-16866	Not reported

[Debian bug #941692]

OpenFactory catalog packages

Matching against OpenFactory catalog package versions is in progress.

[Debian 12 (Bookworm)]

[libunbound8]Unknown
Source package: [unbound]
Details (4)
- 1.17.1-2+deb12u4 · amd64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u4 · arm64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · amd64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · arm64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
[libunbound-dev]Unknown
Source package: [unbound]
Details (4)
- 1.17.1-2+deb12u4 · amd64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u4 · arm64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · amd64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · arm64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
[python3-unbound]Unknown
Source package: [unbound]
Details (4)
- 1.17.1-2+deb12u4 · amd64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u4 · arm64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · amd64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · arm64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
[unbound]Unknown
Details (4)
- 1.17.1-2+deb12u4 · amd64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u4 · arm64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · amd64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · arm64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
[unbound-anchor]Unknown
Source package: [unbound]
Details (4)
- 1.17.1-2+deb12u4 · amd64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u4 · arm64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · amd64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · arm64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
[unbound-host]Unknown
Source package: [unbound]
Details (4)
- 1.17.1-2+deb12u4 · amd64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u4 · arm64 · bookworm
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · amd64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12
- 1.17.1-2+deb12u3 · arm64 · bookworm-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · bookworm; nvd · unbound · debian · 12

[Debian 13 (Trixie)]

[libunbound8]Unknown
Source package: [unbound]
Details (6)
- 1.22.0-2+deb13u3 · amd64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.1-0+deb13u1 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.2-0+deb13u1 · amd64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
[libunbound-dev]Unknown
Source package: [unbound]
Details (6)
- 1.22.0-2+deb13u3 · amd64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.1-0+deb13u1 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.2-0+deb13u1 · amd64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
[python3-unbound]Unknown
Source package: [unbound]
Details (6)
- 1.22.0-2+deb13u3 · amd64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.1-0+deb13u1 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.2-0+deb13u1 · amd64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
[unbound]Unknown
Details (6)
- 1.22.0-2+deb13u3 · amd64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.1-0+deb13u1 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.2-0+deb13u1 · amd64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
[unbound-anchor]Unknown
Source package: [unbound]
Details (6)
- 1.22.0-2+deb13u3 · amd64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.1-0+deb13u1 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.2-0+deb13u1 · amd64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
[unbound-host]Unknown
Source package: [unbound]
Details (6)
- 1.22.0-2+deb13u3 · amd64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.22.0-2+deb13u3 · arm64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.1-0+deb13u1 · amd64 · trixie-security · Historical version
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13
- 1.26.2-0+deb13u1 · amd64 · trixie-security
  Fixed · Fixed: 1.9.4-1
  nvd · unbound · debian · 13

Observed: Oct 23, 2026, 5:41:32 PM UTC

References

[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]