Description
NLnet Labs ldns 1.2.0 up to and including versions 1.9.0, when used in applications as (stub) resolver over UDP, lacks matching the query destination address and port with the response source address and port. Furthermore not the query ID, neither the question of the query is matched with that of the response. This makes applications, that use ldns for (stub) resolver functionality over UDP, vulnerable for off-path poisoning attacks. The drill tool, which is shipped with ldns, suffers from this vulnerability.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| NLnet Labs | ldns | 1.2.0 – < 1.9.1 | 1.9.1 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | ldns | 1.9.2-1 | — |
| Debian 13 | ldns | No fix yet | — |
| Debian 12 | ldns | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | ldns | No fix yet | — |
| Ubuntu 25.10 | ldns | No fix yet | — |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | ldns | 1.8.4-2ubuntu0.26.04.1~esm1 | — |
| Ubuntu Pro 24.04 LTS | ldns | 1.8.3-2ubuntu0.1~esm1 | — |
| Ubuntu Pro 22.04 LTS | ldns | 1.7.1-2ubuntu4+esm2 | — |
| Ubuntu Pro 20.04 LTS | ldns | 1.7.0-4.1ubuntu1+esm2 | — |
| Ubuntu Pro 18.04 LTS | ldns | 1.7.0-3ubuntu4.1+esm1 | — |
| Ubuntu Pro 16.04 LTS | ldns | 1.6.17-8ubuntu0.1+esm2 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | ldns +5 | 1.8.3-18.el10_2.1 | RHSA-2026:49836 |
| RHEL 9 | ldns +5 | 1.7.1-12.el9_8.1 | RHSA-2026:50108 |
| RHEL 8 | ldns +5 | 1.7.0-23.el8_10 | RHSA-2026:49520 |
Show 11 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10.0 EUS | ldns +2 | 1.8.3-18.el10_0.1 | RHSA-2026:53402 |
| RHEL 9.6 EUS | ldns +2 | 1.7.1-12.el9_6.1 | RHSA-2026:54254 |
| RHEL 9.4 E4S | ldns | 1.7.1-11.el9_4.1 | RHSA-2026:54244 |
| RHEL 9.2 E4S | ldns | 1.7.1-11.el9_2.1 | RHSA-2026:54377 |
| RHEL 8.8 TUS | ldns | 1.7.0-21.el8_8.1 | RHSA-2026:98132 |
| RHEL 8.8 E4S | ldns | 1.7.0-21.el8_8.1 | RHSA-2026:98132 |
| RHEL 8.6 EUS Long Life | ldns | 1.7.0-21.el8_6.1 | RHSA-2026:98948 |
| RHEL 8.6 AUS | ldns | 1.7.0-21.el8_6.1 | RHSA-2026:98948 |
| RHEL 8.4 EUS Long Life | ldns | 1.7.0-21.el8_4.1 | RHSA-2026:98949 |
| RHEL 8.4 AUS | ldns | 1.7.0-21.el8_4.1 | RHSA-2026:98949 |
| RHEL 7 ELS | ldns | 1.6.16-10.el7_9.1 | RHSA-2026:98131 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | ldns +5 | 1.8.3-18.el10_2.1 | ALSA-2026:49836 |
| AlmaLinux 9 | ldns +5 | 1.7.1-12.el9_8.1 | ALSA-2026:50108 |
| AlmaLinux 8 | ldns +5 | 1.7.0-23.el8_10 | ALSA-2026:49520 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | ldns | 1.8.3-18.el10_2.1 | RLSA-2026:49836 |
| Rocky Linux 9 | ldns | 1.7.1-12.el9_8.1 | RLSA-2026:50108 |
| Rocky Linux 8 | ldns | 1.7.0-23.el8_10 | RLSA-2026:49520 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | ldns | 1.8.3-150600.3.3.1 | SUSE-SU-2026:2462-1 |
| SLES 15 SP6 | ldns | 1.8.3-150600.3.3.1 | SUSE-SU-2026:2462-1 |
| SLES 15 SP5 | ldns | 1.7.0-150000.4.11.1 | SUSE-SU-2026:2461-1 |
| SLES 15 SP4 | ldns | 1.7.0-150000.4.11.1 | SUSE-SU-2026:2461-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | ldns | 1.8.4-160000.3.1 | SUSE-SU-2026:22167-1 |
| SLES for SAP 15 SP6 | ldns | 1.8.3-150600.3.3.1 | SUSE-SU-2026:2462-1 |
| SLES for SAP 15 SP5 | ldns | 1.7.0-150000.4.11.1 | SUSE-SU-2026:2461-1 |
| SLES for SAP 15 SP4 | ldns | 1.7.0-150000.4.11.1 | SUSE-SU-2026:2461-1 |
| SLES 16.0 | ldns | 1.8.4-160000.3.1 | SUSE-SU-2026:22167-1 |
| SLE HPC 15 SP5 | ldns | 1.7.0-150000.4.11.1 | SUSE-SU-2026:2461-1 |
| SLE HPC 15 SP4 | ldns | 1.7.0-150000.4.11.1 | SUSE-SU-2026:2461-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | ldns | 1.9.2-1.1 | openSUSE-SU-2026:10998-1 |
| openSUSE Leap 16.0 | ldns | 1.8.4-160000.3.1 | openSUSE-SU-2026:21093-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | ldns | 1.8.3-3 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | ldns +5 | 1.8.3-18.el10_2.1 | ELSA-2026-49836 |
| Oracle Linux 8 | ldns +5 | 1.7.0-23.el8_10 | ELSA-2026-49520 |
Advisories 26
- RHSA-2026:98949 Red Hat Security Advisory: ldns security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:98948 Red Hat Security Advisory: ldns security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:98132 Red Hat Security Advisory: ldns security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:98131 Red Hat Security Advisory: ldns security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- WID-SEC-2026-1871 FreeBSD Project FreeBSD OS: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 11, 2026
- ALSA-2026:50108 Important: ldns security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:49836 Important: ldns security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:49520 Important: ldns security update AlmaLinux Security Advisories · Oct 29, 2026
- WID-SEC-2026-3043 IBM QRadar SIEM: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 17, 2026
- RHSA-2026:54377 Red Hat Security Advisory: ldns security update Red Hat Security Advisories (RHSA) · Aug 22, 2026
- RHSA-2026:54244 Red Hat Security Advisory: ldns security update Red Hat Security Advisories (RHSA) · Aug 22, 2026
- RHSA-2026:54254 Red Hat Security Advisory: ldns security update Red Hat Security Advisories (RHSA) · Aug 22, 2026
- RHSA-2026:53402 Red Hat Security Advisory: ldns security update Red Hat Security Advisories (RHSA) · Aug 22, 2026
- RHSA-2026:50108 Red Hat Security Advisory: ldns security update Red Hat Security Advisories (RHSA) · Aug 22, 2026
- RHSA-2026:49836 Red Hat Security Advisory: ldns security update Red Hat Security Advisories (RHSA) · Aug 22, 2026
- RHSA-2026:49520 Red Hat Security Advisory: ldns security update Red Hat Security Advisories (RHSA) · Aug 22, 2026
- RLSA-2026:49836 Important: ldns security update Rocky Linux Security Advisories · Aug 6, 2026
- RLSA-2026:50108 Important: ldns security update Rocky Linux Security Advisories · Aug 6, 2026
- RLSA-2026:49520 Important: ldns security update Rocky Linux Security Advisories · Aug 4, 2026
- ELSA-2026-49520 Important: ldns security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Aug 4, 2026
- ELSA-2026-49836 Important: ldns security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Aug 3, 2026
- openSUSE-SU-2026:21093-1 Security update for ldns SUSE / openSUSE Security Updates · Jun 30, 2026
- SUSE-SU-2026:22167-1 Security update for ldns SUSE / openSUSE Security Updates · Jun 24, 2026
- SUSE-SU-2026:2462-1 Security update for ldns SUSE / openSUSE Security Updates · Jun 20, 2026
- SUSE-SU-2026:2461-1 Security update for ldns SUSE / openSUSE Security Updates · Jun 20, 2026
- openSUSE-SU-2026:10998-1 ldns-1.9.2-1.1 on GA media SUSE / openSUSE Security Updates · Jun 12, 2026
References
- https://www.nlnetlabs.nl/downloads/ldns/CVE-2026-10846.txt vendor-advisory