Description
An issue has been found in dnsdist before 1.2.0 in the way EDNS0 OPT records are handled when parsing responses from a backend. When dnsdist is configured to add EDNS Client Subnet to a query, the response may contain an EDNS0 OPT record that has to be removed before forwarding the response to the initial client. On a 32-bit system, the pointer arithmetic used when parsing the received response to remove that record might trigger an undefined behavior leading to a crash.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Open-Xchange | dnsdist | 1.2.0 | — |
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 | dnsdist | 1.2.0-1 | — |
| Debian 13 | dnsdist | 1.2.0-1 | — |
| Debian 12 | dnsdist | 1.2.0-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | dnsdist | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP5 | dnsdist | 1.8.0-150400.9.3.1 | SUSE-SU-2023:2760-2 |
| SLES 15 SP5 | luajit | 2.1.0~beta3+git.1624618403.e9577376-150400.4.2.1 | SUSE-SU-2023:2760-2, SUSE-SU-2023:2760-1 |
| SLES 15 SP4 | dnsdist | 1.8.0-150400.9.3.1 | SUSE-SU-2023:2760-1 |
| SLES 15 SP4 | luajit | 2.1.0~beta3+git.1624618403.e9577376-150400.4.2.1 | SUSE-SU-2023:2760-1 |
| SLES 15 SP3 | dnsdist | 1.8.0-150100.3.5.1 | SUSE-SU-2023:2777-1 |
| SLES 15 SP2 | dnsdist | 1.8.0-150100.3.5.1 | SUSE-SU-2023:2777-1 |
| SLES 15 SP1 | dnsdist | 1.8.0-150100.3.5.1 | SUSE-SU-2023:2777-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP2 | dnsdist | 1.8.0-150100.3.5.1 | SUSE-SU-2023:2777-1 |
| SLES for SAP 15 SP1 | dnsdist | 1.8.0-150100.3.5.1 | SUSE-SU-2023:2777-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | dnsdist | 1.8.0~rc1-1.1 | openSUSE-SU-2024:12731-1 |
| openSUSE Leap 15.5 | dnsdist | 1.8.0-150400.9.3.1 | SUSE-SU-2023:2760-2, SUSE-SU-2023:2760-1 |
| openSUSE Leap 15.5 | luajit | 2.1.0~beta3+git.1624618403.e9577376-150400.4.2.1 | SUSE-SU-2023:2760-2, SUSE-SU-2023:2760-1 |
| openSUSE Leap 15.4 | dnsdist | 1.8.0-150400.9.3.1 | SUSE-SU-2023:2760-2, SUSE-SU-2023:2760-1 |
| openSUSE Leap 15.4 | luajit | 2.1.0~beta3+git.1624618403.e9577376-150400.4.2.1 | SUSE-SU-2023:2760-2, SUSE-SU-2023:2760-1 |
Advisories 4
- SUSE-SU-2023:2760-2 Security update for dnsdist SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:2760-1 Security update for dnsdist SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:2777-1 Security update for dnsdist SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:12731-1 dnsdist-1.8.0~rc1-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026