CVE-2026-82717
Fixed in a distro release EPSS <1%CVSS 8.4
In NLnet Labs Unbound up to and including 1.26.0, a vulnerability was found in that can progressively corrupt heap memory and under certain systems and compilation options could lead to remote code execution. The vulnerability starts when CNAME synthesis during an upstream response needs to enforce(rewrite) a max TTL value in the packet buffer. Coupled with a compression pointer that points to the overwritten value and invalidates the domain name, it leads to an error path that does not properly move the buffer position and allows for the heap buffer overflow. Since this is heavily reliant on heap memory layout, results are memory corruption that eventually leads to a crash and under specific systems and compilation options remote code execution.
Products: NLnet Labs unbound
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| AlmaLinux 10 | python3-unbound | 1.24.2-7.el10_2.6 |
| AlmaLinux 10 | unbound | 1.24.2-7.el10_2.6 |
| AlmaLinux 10 | unbound-anchor | 1.24.2-7.el10_2.6 |
| AlmaLinux 10 | unbound-devel | 1.24.2-7.el10_2.6 |
| AlmaLinux 10 | unbound-dracut | 1.24.2-7.el10_2.6 |
| AlmaLinux 10 | unbound-libs | 1.24.2-7.el10_2.6 |
| AlmaLinux 10 | unbound-utils | 1.24.2-7.el10_2.6 |
| AlmaLinux 8 | python3-unbound | 1.16.2-5.14.el8_10.4 |
| AlmaLinux 8 | unbound | 1.16.2-5.14.el8_10.4 |
| AlmaLinux 8 | unbound-devel | 1.16.2-5.14.el8_10.4 |
| AlmaLinux 8 | unbound-libs | 1.16.2-5.14.el8_10.4 |
| AlmaLinux 9 | python3-unbound | 1.24.2-3.el9_8.8 |
| AlmaLinux 9 | unbound | 1.24.2-3.el9_8.8 |
| AlmaLinux 9 | unbound-devel | 1.24.2-3.el9_8.8 |
| AlmaLinux 9 | unbound-dracut | 1.24.2-3.el9_8.8 |
| AlmaLinux 9 | unbound-libs | 1.24.2-3.el9_8.8 |
| Alpine 3.22 | unbound | 1.25.2-r0 |
| Alpine 3.23 | unbound | 1.25.2-r0 |
| Alpine 3.24 | unbound | 1.25.2-r2 |
| Amazon Linux 2 | python2-unbound | 1.7.3-15.amzn2.0.17 |
| Amazon Linux 2 | python3-unbound | 1.7.3-15.amzn2.0.17 |
| Amazon Linux 2 | unbound | 1.7.3-15.amzn2.0.17 |
| Amazon Linux 2 | unbound-devel | 1.7.3-15.amzn2.0.17 |
| Amazon Linux 2 | unbound-libs | 1.7.3-15.amzn2.0.17 |
| Amazon Linux 2023 | python3-unbound | 1.17.1-1.amzn2023.0.15 |
| Amazon Linux 2023 | unbound | 1.17.1-1.amzn2023.0.15 |
| Amazon Linux 2023 | unbound-anchor | 1.17.1-1.amzn2023.0.15 |
| Amazon Linux 2023 | unbound-devel | 1.17.1-1.amzn2023.0.15 |
| Amazon Linux 2023 | unbound-libs | 1.17.1-1.amzn2023.0.15 |
| Amazon Linux 2023 | unbound-utils | 1.17.1-1.amzn2023.0.15 |
| Debian 12 | unbound | no fix |
| Debian 13 | unbound | 1.26.1-0+deb13u1 |
| Debian 14 | unbound | 1.26.1-1 |
| Red Hat Enterprise Linux 10.2 | python3-unbound | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | python3-unbound-debuginfo | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | unbound | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | unbound-anchor | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | unbound-anchor-debuginfo | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | unbound-debuginfo | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | unbound-debugsource | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | unbound-devel | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | unbound-dracut | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | unbound-libs | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | unbound-libs-debuginfo | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | unbound-utils | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | unbound-utils-debuginfo | 0:1.24.2-7.el10_2.6 |
| Red Hat Enterprise Linux 8 | python3-unbound | 0:1.16.2-5.14.el8_10.4 |
| Red Hat Enterprise Linux 8 | python3-unbound-debuginfo | 0:1.16.2-5.14.el8_10.4 |
| Red Hat Enterprise Linux 8 | unbound | 0:1.16.2-5.14.el8_10.4 |
| Red Hat Enterprise Linux 8 | unbound-debuginfo | 0:1.16.2-5.14.el8_10.4 |
| Red Hat Enterprise Linux 8 | unbound-debugsource | 0:1.16.2-5.14.el8_10.4 |
| Red Hat Enterprise Linux 8 | unbound-devel | 0:1.16.2-5.14.el8_10.4 |
| Red Hat Enterprise Linux 8 | unbound-libs | 0:1.16.2-5.14.el8_10.4 |
| Red Hat Enterprise Linux 8 | unbound-libs-debuginfo | 0:1.16.2-5.14.el8_10.4 |
| Red Hat Enterprise Linux 9 | python3-unbound | 0:1.24.2-3.el9_8.8 |
| Red Hat Enterprise Linux 9 | python3-unbound-debuginfo | 0:1.24.2-3.el9_8.8 |
| Red Hat Enterprise Linux 9 | unbound | 0:1.24.2-3.el9_8.8 |
| Red Hat Enterprise Linux 9 | unbound-debuginfo | 0:1.24.2-3.el9_8.8 |
| Red Hat Enterprise Linux 9 | unbound-debugsource | 0:1.24.2-3.el9_8.8 |
| Red Hat Enterprise Linux 9 | unbound-devel | 0:1.24.2-3.el9_8.8 |
| Red Hat Enterprise Linux 9 | unbound-dracut | 0:1.24.2-3.el9_8.8 |
| Red Hat Enterprise Linux 9 | unbound-libs | 0:1.24.2-3.el9_8.8 |
| Red Hat Enterprise Linux 9 | unbound-libs-debuginfo | 0:1.24.2-3.el9_8.8 |
| Red Hat hummingbird 1 | python3-unbound | 0:1.26.1-1.hum1 |
| Red Hat hummingbird 1 | unbound | 0:1.26.1-1.hum1 |
| Red Hat hummingbird 1 | unbound-anchor | 0:1.26.1-1.hum1 |
| Red Hat hummingbird 1 | unbound-devel | 0:1.26.1-1.hum1 |
| Red Hat hummingbird 1 | unbound-dracut | 0:1.26.1-1.hum1 |
| Red Hat hummingbird 1 | unbound-libs | 0:1.26.1-1.hum1 |
| Red Hat hummingbird 1 | unbound-munin | 0:1.26.1-1.hum1 |
| Red Hat hummingbird 1 | unbound-utils | 0:1.26.1-1.hum1 |
| Rocky Linux 10 | unbound | 0:1.24.2-7.el10_2.6 |
| Rocky Linux 8 | unbound | 0:1.16.2-5.14.el8_10.4 |
| Rocky Linux 9 | unbound | 0:1.24.2-3.el9_8.8 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | unbound | 1.26.1-150100.10.31.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | unbound | 1.26.1-150100.10.31.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | unbound | 1.26.1-150100.10.31.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | unbound | 1.26.1-150100.10.31.1 |
| SUSE Linux Enterprise Micro 5.5 | unbound | 1.26.1-150100.10.31.1 |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | unbound | 1.26.1-150600.23.24.1 |
| SUSE Linux Enterprise Module for Package Hub 15 SP7 | unbound | 1.26.1-150600.23.24.1 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | unbound | 1.26.1-150100.10.31.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | unbound | 1.26.1-150100.10.31.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | unbound | 1.26.1-150600.23.24.1 |
| SUSE Linux Enterprise Server 16.0 | unbound | 1.26.1-160000.1.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | unbound | 1.26.1-150100.10.31.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | unbound | 1.26.1-150100.10.31.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | unbound | 1.26.1-150600.23.24.1 |
| SUSE Linux Enterprise Server for SAP applications 16.0 | unbound | 1.26.1-160000.1.1 |
| SUSE Linux Micro 6.0 | unbound | 1.26.1-159998.1.1 |
| SUSE Linux Micro 6.2 | unbound | 1.26.1-160000.1.1 |
| Ubuntu 22.04 LTS | unbound | 1.13.1-1ubuntu5.16 |
| Ubuntu 24.04 LTS | unbound | 1.19.2-1ubuntu3.10 |
| Ubuntu 26.04 LTS | unbound | 1.24.2-1ubuntu2.3 |
| Ubuntu 26.10 | unbound | no fix |
| Ubuntu Pro 14.04 LTS | unbound | 1.4.22-1ubuntu4.14.04.3+esm4 |
| Ubuntu Pro 16.04 LTS | unbound | 1.5.8-1ubuntu1.1+esm4 |
| Ubuntu Pro 18.04 LTS | unbound | 1.6.7-1ubuntu2.6+esm5 |
| Ubuntu Pro 20.04 LTS | unbound | 1.9.4-2ubuntu1.11+esm2 |
| openSUSE Leap 16.0 | unbound | 1.26.1-160000.1.1 |
| openSUSE Tumbleweed | unbound | 1.26.1-1.1 |