CVE-2026-12490
Bypass of client certificate verification with transfer over TLS
When a provide-xfr is given with a tls-auth-name, a secondary requesting a transfer should provide a client certificate with that name. However, no client certificate is needed when the request comes in over TLS over the regular tls-port (and not the tls-auth-port) or over over TCP over the regular port, when the other conditions of the provide-xfr rule match.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Bypass of client certificate verification with transfer over TLS
When a provide-xfr is given with a tls-auth-name, a secondary requesting a transfer should provide a client certificate with that name. However, no client certificate is needed when the request comes in over TLS over the regular tls-port (and not the tls-auth-port) or over over TCP over the regular port, when the other conditions of the provide-xfr rule match.
- Record
CVE-2026-12490- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-306, CWE-284
- Updated
- 2026-11-02
EUVDEUVD-2026-39185
When a provide-xfr is given with a tls-auth-name, a secondary requesting a transfer should provide a client certificate with that name. However, no client certificate is needed when the request comes in over TLS over the regular tls-port (and not the tls-auth-port) or over over TCP over the regular port, when the other conditions of the provide-xfr rule match.
- Record
EUVD-2026-39185- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-27xx-c7vg-hjjj
When a provide-xfr is given with a tls-auth-name, a secondary requesting a transfer should...
When a provide-xfr is given with a tls-auth-name, a secondary requesting a transfer should provide a client certificate with that name. However, no client certificate is needed when the request comes in over TLS over the regular tls-port (and not the tls-auth-port) or over over TCP over the regular port, when the other conditions of the provide-xfr rule match.
- Record
GHSA-27xx-c7vg-hjjj- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/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
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-284
- Updated
- 2026-11-02
NVD
When a provide-xfr is given with a tls-auth-name, a secondary requesting a transfer should provide a client certificate with that name. However, no client certificate is needed when the request comes in over TLS over the regular tls-port (and not the tls-auth-port) or over over TCP over the regular port, when the other conditions of the provide-xfr rule match.
- Record
CVE-2026-12490- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/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
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-284, CWE-306
- Updated
- 2026-11-02
OSVALPINE-CVE-2026-12490
When a provide-xfr is given with a tls-auth-name, a secondary requesting a transfer should provide a client certificate with that name. However, no client certificate is needed when the request comes in over TLS over the regular tls-port (and not the tls-auth-port) or over over TCP over the regular port, when the other conditions of the provide-xfr rule match.
- Record
ALPINE-CVE-2026-12490- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSV
When a provide-xfr is given with a tls-auth-name, a secondary requesting a transfer should provide a client certificate with that name. However, no client certificate is needed when the request comes in over TLS over the regular tls-port (and not the tls-auth-port) or over over TCP over the regular port, when the other conditions of the provide-xfr rule match.
- Record
CVE-2026-12490- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
Show 4 moreShow less
OSVDEBIAN-CVE-2026-12490
When a provide-xfr is given with a tls-auth-name, a secondary requesting a transfer should provide a client certificate with that name. However, no client certificate is needed when the request comes in over TLS over the regular tls-port (and not the tls-auth-port) or over over TCP over the regular port, when the other conditions of the provide-xfr rule match.
- Record
DEBIAN-CVE-2026-12490- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-12490
When a provide-xfr is given with a tls-auth-name, a secondary requesting a transfer should provide a client certificate with that name. However, no client certificate is needed when the request comes in over TLS over the regular tls-port (and not the tls-auth-port) or over over TCP over the regular port, when the other conditions of the provide-xfr rule match.
- Record
UBUNTU-CVE-2026-12490- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - 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 |
before 4.14.3-r0 | 4.14.3-r0 |
nsdDebian:12 |
All versions, plus listed versions 4.10.1-14.10.1~rc2-14.10.1~rc2-24.11.0-14.11.1-1 Show 22 moreShow less4.12.0-14.12.0-24.13.0-14.13.0-24.13.0-34.13.0-44.13.0-54.13.0-64.14.0-14.14.1-14.14.2-14.14.3-14.15.0-14.15.0~rc1-14.15.1-14.15.2-14.15.3-14.15.4-14.6.1-14.7.0-14.8.0-14.9.1-1 |
None known |
nsdDebian:13 |
All versions, plus listed versions 4.12.0-14.12.0-24.13.0-14.13.0-24.13.0-3 Show 13 moreShow less4.13.0-44.13.0-54.13.0-64.14.0-14.14.1-14.14.2-14.14.3-14.15.0-14.15.0~rc1-14.15.1-14.15.2-14.15.3-14.15.4-1 |
None known |
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: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-2026-12490 is a high vulnerability (CVSS 8.2) 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 0.22%, the 12th percentile. Fixed in nsd 4.14.3-r0.
References
nlnetlabs.nl/downloads/nsd/CVE-2026-12490.txt
nvd.nist.gov/vuln/detail/CVE-2026-12490
github.com/advisories/GHSA-27xx-c7vg-hjjj
security.alpinelinux.org/vuln/CVE-2026-12490
security-tracker.debian.org/tracker/CVE-2026-12490
ubuntu.com/security/CVE-2026-12490
Show 10 moreShow less
cve.org/CVERecord?id=CVE-2026-12490
suse.com/security/cve/CVE-2026-12244
bugzilla.suse.com/1269563