CVE-2026-12246
Out of bounds stack write with crafted APL RR
NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger than permitted for the address family will overwrite the stack when the zone is written to disk, with a maximum of 111 attacker controlled bytes.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Out of bounds stack write with crafted APL RR
NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger than permitted for the address family will overwrite the stack when the zone is written to disk, with a maximum of 111 attacker controlled bytes.
- Record
CVE-2026-12246- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-120, CWE-20
- Updated
- 2026-11-02
EUVDEUVD-2026-39184
NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger than permitted for the address family will overwrite the stack when the zone is written to disk, with a maximum of 111 attacker controlled bytes.
- Record
EUVD-2026-39184- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-xgm5-85mh-3559
NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger...
NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger than permitted for the address family will overwrite the stack when the zone is written to disk, with a maximum of 111 attacker controlled bytes.
- Record
GHSA-xgm5-85mh-3559- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-20
- Updated
- 2026-11-02
NVD
NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger than permitted for the address family will overwrite the stack when the zone is written to disk, with a maximum of 111 attacker controlled bytes.
- Record
CVE-2026-12246- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-20, CWE-120
- Updated
- 2026-11-02
OSVALPINE-CVE-2026-12246
NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger than permitted for the address family will overwrite the stack when the zone is written to disk, with a maximum of 111 attacker controlled bytes.
- Record
ALPINE-CVE-2026-12246- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H - Updated
- 2026-11-02
OSV
NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger than permitted for the address family will overwrite the stack when the zone is written to disk, with a maximum of 111 attacker controlled bytes.
- Record
CVE-2026-12246- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H - Updated
- 2026-11-02
Show 4 moreShow less
OSVDEBIAN-CVE-2026-12246
NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger than permitted for the address family will overwrite the stack when the zone is written to disk, with a maximum of 111 attacker controlled bytes.
- Record
DEBIAN-CVE-2026-12246- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-12246
NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger than permitted for the address family will overwrite the stack when the zone is written to disk, with a maximum of 111 attacker controlled bytes.
- Record
UBUNTU-CVE-2026-12246- CVSS 4.0
- 7.2 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H - Updated
- 2026-11-02
OSVopenSUSE-SU-2026:11395-1 No score
nsd-4.14.3-1.1 on GA media
These are all security issues fixed in the nsd-4.14.3-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2026:11395-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2026:21502-1 No score
Security update for nsd
This update for nsd fixes the following issues:
Changes in nsd:
-
Update nsd.keyring
-
update to 4.14.3: https://github.com/NLnetLabs/nsd/blob/NSD_4_14_3_REL/doc/ChangeLog
- CVE-2026-12490: Bypass of client certificate verification with transfer over TLS (bsc#1269563)
- CVE-2026-12246: Out of bounds stack write with crafted APL RR (bsc#1269564)
- CVE-2026-12245: Denial of DNS over TLS service by any DoT client (bsc#1269565)
- CVE-2026-12244: Heap overflow and crash with crafted SVCB RR (bsc#1269566)
-
update to 4.14.2: https://github.com/NLnetLabs/nsd/blob/NSD_4_14_2_REL/doc/ChangeLog
-
update to 4.14.1: https://github.com/NLnetLabs/nsd/blob/NSD_4_14_1_REL/doc/ChangeLog
-
update to 4.14.0: https://github.com/NLnetLabs/nsd/blob/NSD_4_14_0_REL/doc/ChangeLog
-
update to 4.13.0: https://github.com/NLnetLabs/nsd/blob/NSD_4_13_0_REL/doc/ChangeLog https://github.com/NLnetLabs/nsd/blob/NSD_4_12_1_REL/doc/ChangeLog https://github.com/NLnetLabs/nsd/blob/NSD_4_12_0_REL/doc/ChangeLog https://github.com/NLnetLabs/nsd/blob/NSD_4_11_1_REL/doc/ChangeLog https://github.com/NLnetLabs/nsd/blob/NSD_4_11_0_REL/doc/ChangeLog https://github.com/NLnetLabs/nsd/blob/NSD_4_10_1_REL/doc/ChangeLog https://github.com/NLnetLabs/nsd/blob/NSD_4_10_0_REL/doc/ChangeLog https://github.com/NLnetLabs/nsd/blob/NSD_4_9_1_REL/doc/ChangeLog https://github.com/NLnetLabs/nsd/blob/NSD_4_9_0_REL/doc/ChangeLog
-
enable systemd notify support.
-
enable dnstap support.
-
enable tcp fast open support
-
enable support for >= 2038
- Record
openSUSE-SU-2026:21502-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
nsdAlpine:v3.24 |
4.14.0 up to 4.14.3-r0 | 4.14.3-r0 |
nsdDebian:14 |
before 4.14.3-1, plus listed versions 4.12.0-14.12.0-24.13.0-14.13.0-24.13.0-3 Show 6 moreShow less4.13.0-44.13.0-54.13.0-64.14.0-14.14.1-14.14.2-1 |
4.14.3-1 |
nsdUbuntu:Pro:16.04:LTS |
before 4.1.7-1ubuntu0.1~esm1, plus listed versions 4.1.2-14.1.6-14.1.7-1 |
4.1.7-1ubuntu0.1~esm1 |
nsdUbuntu:Pro:18.04:LTS |
before 4.1.17-1ubuntu0.1~esm1, plus listed versions 4.1.16-1build14.1.17-14.1.17-1build1 |
4.1.17-1ubuntu0.1~esm1 |
nsdUbuntu:Pro:20.04:LTS |
before 4.1.26-1ubuntu0.1~esm1, plus listed versions 4.1.26-14.1.26-1build1 |
4.1.26-1ubuntu0.1~esm1 |
nsdUbuntu:Pro:22.04:LTS |
before 4.3.9-1ubuntu0.1~esm1, plus listed versions 4.3.5-14.3.7-14.3.8-14.3.8-1build14.3.9-1 |
4.3.9-1ubuntu0.1~esm1 |
nsdUbuntu:Pro:24.04:LTS |
before 4.8.0-1ubuntu0.1~esm1, plus listed versions 4.7.0-14.8.0-14.8.0-1build14.8.0-1build3 |
4.8.0-1ubuntu0.1~esm1 |
nsdUbuntu:25.10 |
All versions, plus listed versions 4.11.1-14.12.0-1 |
None known |
nsdUbuntu:26.10 |
All versions, plus listed versions 4.14.0-14.14.2-14.14.3-14.15.0-14.15.0-1build1 |
None known |
nsdUbuntu:Pro:26.04:LTS |
before 4.14.0-1ubuntu0.1~esm1, plus listed versions 4.12.0-14.13.0-64.14.0-1 |
4.14.0-1ubuntu0.1~esm1 |
nsdopenSUSE:Tumbleweed From an advisory covering 4 CVEs |
before 4.14.3-1.1 | 4.14.3-1.1 |
nsdopenSUSE:Leap 16.0 From an advisory covering 4 CVEs |
before 4.14.3-bp160.1.1 | 4.14.3-bp160.1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-12246 is a high vulnerability (CVSS 7.2) in Nlnet Labs Nsd, published June 25, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.44%, the 38th percentile. Fixed in nsd 4.14.3-r0.
References
nlnetlabs.nl/downloads/nsd/CVE-2026-12246.txt
nvd.nist.gov/vuln/detail/CVE-2026-12246
github.com/advisories/GHSA-xgm5-85mh-3559
security.alpinelinux.org/vuln/CVE-2026-12246
security-tracker.debian.org/tracker/CVE-2026-12246
ubuntu.com/security/CVE-2026-12246
Show 10 moreShow less
cve.org/CVERecord?id=CVE-2026-12246
suse.com/security/cve/CVE-2026-12244
bugzilla.suse.com/1269563