Description
If a BIND resolver is performing DNSSEC validation and encounters a maliciously crafted zone, the resolver may consume excessive CPU. Authoritative-only servers are generally unaffected, although there are circumstances where authoritative servers may make recursive queries (see: https://kb.isc.org/docs/why-does-my-authoritative-server-make-recursive-queries).
This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.46, 9.20.0 through 9.20.20, 9.21.0 through 9.21.19, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.46-S1, and 9.20.9-S1 through 9.20.20-S1.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| ISC | BIND 9 | 9.11.0 – ≤ 9.16.50, 9.18.0 – ≤ 9.18.46, 9.20.0 – ≤ 9.20.20, 9.21.0 – ≤ 9.21.19, 9.11.3-S1 – ≤ 9.16.50-S1, 9.18.11-S1 – ≤ 9.18.46-S1, 9.20.9-S1 – ≤ 9.20.20-S1 | — |
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 | bind9 | 1:9.20.21-1 | — |
| Debian 13 | bind9 | 1:9.20.21-1~deb13u1 | DSA-6181-1 |
| Debian 12 | bind9 | 1:9.18.47-1~deb12u1 | DSA-6181-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | bind9 | 1:9.20.24-1ubuntu0.4 | USN-8929-1 |
| Ubuntu 26.04 LTS | isc-dhcp | No fix yet | — |
| Ubuntu 25.10 | bind9 | 1:9.20.11-1ubuntu2.2 | — |
| Ubuntu 25.10 | isc-dhcp | No fix yet | — |
| Ubuntu 24.04 LTS | bind9 | 1:9.18.39-0ubuntu0.24.04.3 | USN-8929-1 |
| Ubuntu 24.04 LTS | isc-dhcp | No fix yet | — |
| Ubuntu 22.04 LTS | bind9 | 1:9.18.39-0ubuntu0.22.04.3 | USN-8929-1 |
| Ubuntu 22.04 LTS | bind9-libs | No fix yet | — |
| Ubuntu 20.04 LTS | bind9-libs | No fix yet | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | isc-dhcp | No fix yet | — |
| Ubuntu Pro 20.04 LTS | bind9 | 1:9.18.30-0ubuntu0.20.04.2+esm3 | USN-8929-1 |
| Ubuntu Pro 18.04 LTS | bind9 | 1:9.11.3+dfsg-1ubuntu1.19+esm6 | USN-8929-1 |
| Ubuntu Pro 16.04 LTS | bind9 | 1:9.10.3.dfsg.P4-8ubuntu1.19+esm11 | USN-8929-1 |
| Ubuntu Pro 14.04 LTS | bind9 | 1:9.9.5.dfsg-3ubuntu0.19+esm15 | USN-8929-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | bind +7 | 32:9.18.33-10.el10_1.3 | RHSA-2026:8312 |
| RHEL 9 | bind +9 | 32:9.16.23-34.el9_7.2 | RHSA-2026:8075 |
| RHEL 9 | bind9.18 +6 | 32:9.18.29-5.el9_7.4 | RHSA-2026:7915 |
| RHEL 8 | bind +16 | 32:9.11.36-16.el8_10.7 | RHSA-2026:8352 |
| RHEL 8 | bind9.16 +8 | 32:9.16.23-0.22.el8_10.5 | RHSA-2026:8155 |
Show 15 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10.0 EUS | bind +1 | 32:9.18.33-4.el10_0.3 | RHSA-2026:24851 |
| RHEL 9.6 EUS | bind +1 | 32:9.16.23-31.el9_6.3 | RHSA-2026:24500 |
| RHEL 9.6 EUS | bind9.18 +1 | 32:9.18.29-4.el9_6.3 | RHSA-2026:24934 |
| RHEL 9.4 E4S | bind +1 | 32:9.16.23-18.el9_4.11 | RHSA-2026:25214 |
| RHEL 9.2 E4S | bind +1 | 32:9.16.23-11.el9_2.10 | RHSA-2026:29110 |
| RHEL 8.8 TUS | bind +16 | 32:9.11.36-8.el8_8.9 | RHSA-2026:15890 |
| RHEL 8.8 TUS | bind9.16 +1 | 32:9.16.23-0.14.el8_8.8 | RHSA-2026:25083 |
| RHEL 8.8 E4S | bind +16 | 32:9.11.36-8.el8_8.9 | RHSA-2026:15890 |
| RHEL 8.8 E4S | bind9.16 +1 | 32:9.16.23-0.14.el8_8.8 | RHSA-2026:25083 |
| RHEL 8.6 TUS | bind +16 | 32:9.11.36-3.el8_6.12 | RHSA-2026:16060 |
| RHEL 8.6 EUS Long Life | bind9.16 +1 | 32:9.16.23-0.7.el8_6.10 | RHSA-2026:25171 |
| RHEL 8.6 E4S | bind +16 | 32:9.11.36-3.el8_6.12 | RHSA-2026:16060 |
| RHEL 8.6 AUS | bind +16 | 32:9.11.36-3.el8_6.12 | RHSA-2026:16060 |
| RHEL 8.6 AUS | bind9.16 +1 | 32:9.16.23-0.7.el8_6.10 | RHSA-2026:25171 |
| RHEL 8.4 EUS Long Life | bind +11 | 32:9.11.26-4.el8_4.9 | RHSA-2026:16064 |
| RHEL 8.4 AUS | bind +11 | 32:9.11.26-4.el8_4.9 | RHSA-2026:16064 |
| RHEL 7 ELS | bind +12 | 32:9.11.4-26.P2.el7_9.20 | RHSA-2026:11371 |
| RHEL 6 ELS | bind +3 | 32:9.8.2-0.68.rc1.el6_10.18 | RHSA-2026:11372 |
| Red Hat Hardened Images 1 | bind +6 | 9.18.48-1.hum1 | RHSA-2026:6935 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | bind-doc +1 | 32:9.18.33-10.el10_1.3 | ALSA-2026:8312 |
| AlmaLinux 9 | bind +9 | 32:9.16.23-34.el9_7.2 | ALSA-2026:8075 |
| AlmaLinux 9 | bind9.18 +6 | 32:9.18.29-5.el9_7.4 | ALSA-2026:7915 |
| AlmaLinux 8 | bind +16 | 32:9.11.36-16.el8_10.7 | ALSA-2026:8352 |
| AlmaLinux 8 | bind9.16 +8 | 32:9.16.23-0.22.el8_10.5 | ALSA-2026:8155 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | bind | 2:9.18.33-10.el10_1.3 | RLSA-2026:8312 |
| Rocky Linux 9 | bind | 2:9.16.23-34.el9_7.2 | RLSA-2026:8075 |
| Rocky Linux 9 | bind9.18 | 2:9.18.29-5.el9_7.4 | RLSA-2026:7915 |
| Rocky Linux 8 | bind | 2:9.11.36-16.el8_10.7 | RLSA-2026:8352 |
| Rocky Linux 8 | bind9.16 | 2:9.16.23-0.22.el8_10.5 | RLSA-2026:8155 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | bind | 9.16.6-150300.22.56.1 | SUSE-SU-2026:1366-1, SUSE-SU-2026:1351-1 |
| SLES 15 SP6 | bind | 9.16.6-150300.22.56.1 | SUSE-SU-2026:1366-1, SUSE-SU-2026:1312-1 |
| SLES 15 SP5 | bind | 9.16.50-150500.8.35.1 | SUSE-SU-2026:1230-1 |
| SLES 15 SP4 | bind | 9.16.50-150400.5.59.1 | SUSE-SU-2026:1428-1 |
| SLES 12 SP5 | bind | 9.11.22-3.68.1 | SUSE-SU-2026:1229-1 |
Show 10 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | bind | 9.20.21-160000.1.1 | SUSE-SU-2026:21204-1 |
| SLES for SAP 15 SP6 | bind | 9.16.6-150300.22.56.1 | SUSE-SU-2026:1366-1, SUSE-SU-2026:1312-1 |
| SLES for SAP 15 SP5 | bind | 9.16.50-150500.8.35.1 | SUSE-SU-2026:1230-1 |
| SLES for SAP 15 SP4 | bind | 9.16.50-150400.5.59.1 | SUSE-SU-2026:1428-1 |
| SLES 16.0 | bind | 9.20.21-160000.1.1 | SUSE-SU-2026:21204-1 |
| SLE Micro 5.5 | bind | 9.16.50-150500.8.35.1 | SUSE-SU-2026:1230-1 |
| SLE HPC 15 SP5 | bind | 9.16.50-150500.8.35.1 | SUSE-SU-2026:1230-1 |
| SLE HPC 15 SP4 | bind | 9.16.50-150400.5.59.1 | SUSE-SU-2026:1428-1 |
| SUSE Multi Linux Manager Tools SLE-Micro-5 | bind | 9.16.6-150000.12.88.1 | SUSE-SU-2026:1209-1 |
| SUSE Manager Client Tools for SLE Micro 5 | bind | 9.16.6-150000.12.88.1 | SUSE-SU-2026:1209-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | bind | 9.20.21-1.1 | openSUSE-SU-2026:10448-1 |
| openSUSE Leap 16.0 | bind | 9.20.21-160000.1.1 | openSUSE-SU-2026:20550-1 |
| openSUSE Leap 15.6 | bind | 9.18.33-150600.3.21.1 | SUSE-SU-2026:1312-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | bind | 9.20.21-r0 | — |
| Alpine v3.23 | bind | 9.20.21-r0 | — |
| Alpine v3.22 | bind | 9.20.21-r0 | — |
| Alpine v3.21 | bind | 9.18.47-r0 | — |
| Alpine v3.20 | bind | 9.18.47-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | bind +7 | 32:9.18.33-1.amzn2023.0.5 | ALAS2023-2026-1533 |
| Amazon Linux 2 | bind +15 | 32:9.11.4-26.P2.amzn2.13.14 | ALAS2-2026-3226 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | bind | 9.20.21-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | bind +7 | 32:9.18.33-10.0.2.el10_1.3 | ELSA-2026-8312 |
| Oracle Linux 9 | bind +9 | 32:9.16.23-34.0.1.el9_7.2 | ELSA-2026-8075 |
| Oracle Linux 9 | bind9.18 +6 | 32:9.18.29-5.el9_7.4 | ELSA-2026-7915 |
| Oracle Linux 8 | bind +16 | 32:9.11.36-16.el8_10.7 | ELSA-2026-8352 |
| Oracle Linux 8 | bind9.16 +8 | 32:9.16.23-0.22.el8_10.5 | ELSA-2026-8155 |
| Oracle Linux 7 | bind +15 | 32:9.11.4-26.0.7.P2.el7_9.16 | ELSA-2026-11371 |
Advisories 50
- ALSA-2026:7915 Important: bind9.18 security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:8075 Important: bind security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:8312 Important: bind security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:8155 Important: bind9.16 security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:8352 Important: bind security update AlmaLinux Security Advisories · Oct 29, 2026
- USN-8929-1 bind9 vulnerabilities Ubuntu Security Notices (USN) · Oct 17, 2026
- WID-SEC-2026-0863 Internet Systems Consortium BIND: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 14, 2026
- RHSA-2026:6935 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- RHSA-2026:8352 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 10, 2026
- RHSA-2026:8312 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 10, 2026
- RHSA-2026:8155 Red Hat Security Advisory: bind9.16 security update Red Hat Security Advisories (RHSA) · Oct 10, 2026
- RHSA-2026:8075 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 10, 2026
- RHSA-2026:7915 Red Hat Security Advisory: bind9.18 security update Red Hat Security Advisories (RHSA) · Oct 10, 2026
- RHSA-2026:29110 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 10, 2026
- RHSA-2026:25214 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2026:25171 Red Hat Security Advisory: bind9.16 security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2026:25083 Red Hat Security Advisory: bind9.16 security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2026:24934 Red Hat Security Advisory: bind9.18 security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2026:24851 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2026:24500 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2026:16064 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2026:16060 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2026:15890 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2026:11372 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2026:11371 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- WID-SEC-2026-1666 IBM QRadar SIEM: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jul 28, 2026
- ELSA-2026-11371 Important: bind security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · May 15, 2026
- SUSE-SU-2026:21204-1 Security update for bind SUSE / openSUSE Security Updates · Apr 22, 2026
- openSUSE-SU-2026:20550-1 Security update for bind SUSE / openSUSE Security Updates · Apr 22, 2026
- ELSA-2026-8312 Important: bind security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Apr 22, 2026
- RLSA-2026:8352 Important: bind security update Rocky Linux Security Advisories · Apr 18, 2026
- SUSE-SU-2026:1428-1 Security update for bind SUSE / openSUSE Security Updates · Apr 18, 2026
- RLSA-2026:8312 Important: bind security update Rocky Linux Security Advisories · Apr 16, 2026
- SUSE-SU-2026:1366-1 Security update for bind SUSE / openSUSE Security Updates · Apr 16, 2026
- SUSE-SU-2026:1351-1 Security update for bind SUSE / openSUSE Security Updates · Apr 16, 2026
- RLSA-2026:8075 Important: bind security update Rocky Linux Security Advisories · Apr 15, 2026
- RLSA-2026:7915 Important: bind9.18 security update Rocky Linux Security Advisories · Apr 15, 2026
- RLSA-2026:8155 Important: bind9.16 security update Rocky Linux Security Advisories · Apr 15, 2026
- SUSE-SU-2026:1312-1 Security update for bind SUSE / openSUSE Security Updates · Apr 15, 2026
- ELSA-2026-8352 Important: bind security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Apr 15, 2026
- ELSA-2026-8155 Important: bind9.16 security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Apr 14, 2026
- ELSA-2026-8075 Important: bind security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Apr 14, 2026
- ELSA-2026-7915 Important: bind9.18 security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Apr 14, 2026
- SUSE-SU-2026:1230-1 Security update for bind SUSE / openSUSE Security Updates · Apr 10, 2026
- SUSE-SU-2026:1229-1 Security update for bind SUSE / openSUSE Security Updates · Apr 10, 2026
- SUSE-SU-2026:1209-1 Security update for bind SUSE / openSUSE Security Updates · Apr 9, 2026
- ALAS2023-2026-1533 Important: bind security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Apr 1, 2026
- ALAS2-2026-3226 Important: bind security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Apr 1, 2026
- openSUSE-SU-2026:10448-1 bind-9.20.21-1.1 on GA media SUSE / openSUSE Security Updates · Mar 29, 2026
- DSA-6181-1 bind9 - security update Debian Security (DSA / DLA) · Mar 27, 2026
References
- CVE-2026-1519 vendor-advisory
- https://downloads.isc.org/isc/bind9/9.18.47 patch
- https://downloads.isc.org/isc/bind9/9.20.21 patch
- https://downloads.isc.org/isc/bind9/9.21.20 patch