# OPENSUSE-SU-2026:21533-1: dnsdist security update

OPENSUSE-SU-2026:21533-1, released August 5, 2026, fixes 7 CVEs in dnsdist (version 1.9.15-160000.1.1). None of them is reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/fix/linux/opensuse-su-2026-21533-1
- Platform: Linux
- Released: Aug 5, 2026
- Priority: Routine (Closes 7 CVEs, none high severity)
- CVEs: 7, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://osv.dev/vulnerability/openSUSE-SU-2026:21533-1

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [dnsdist](https://patchblox.com/security/data/product/linux/dnsdist.md) | opensuse-leap 16.0 | 1.9.15-160000.1.1 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2026-40210](https://patchblox.com/security/data/cve/CVE-2026-40210.md) | Routine | dnsdist: out-of-bounds read when `SetMacAddrAction` is used can lead to uninitialized memory being sent over | 4.8 | 0.0074 |  |
| [CVE-2026-40209](https://patchblox.com/security/data/cve/CVE-2026-40209.md) | Routine | dnsdist: outgoing TCP connections to backend can get stuck until a timeout occurs when specially crafted IXFR | 5.3 | 0.0070 |  |
| [CVE-2026-40211](https://patchblox.com/security/data/cve/CVE-2026-40211.md) | Routine | dnsdist: crafted DNS over HTTP/3 queries can trigger an exception that prevents memory from being freed and can | 5.3 | 0.0070 |  |
| [CVE-2026-42005](https://patchblox.com/security/data/cve/CVE-2026-42005.md) | Routine | dnsdist: crafted web request can cause unlimited memory allocation in the internal web server and lead to a DoS | 4.3 | 0.0063 |  |
| [CVE-2026-40208](https://patchblox.com/security/data/cve/CVE-2026-40208.md) | Routine | dnsdist: processing of DoH3 queries can be delayed via DoH3 GET queries with an invalid DATA frames | 3.7 | 0.0040 |  |
| [CVE-2026-40011](https://patchblox.com/security/data/cve/CVE-2026-40011.md) | Routine | dnsdist: invalid output produced in the prometheus endpoint when a large number of crafted DNS queries are sent | 3.7 | 0.0023 |  |
| [CVE-2026-42004](https://patchblox.com/security/data/cve/CVE-2026-42004.md) | Routine | dnsdist: crafted EDNS OPT record will be ignored by filtering rules, but will be rewritten as a valid OPT | 3.7 | 0.0023 |  |

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Data as of 2026-11-11T13:47:35Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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