# CVE-2026-123581: Hickory DNS through 0.26.0-alpha.1 DNSSEC Validation Bypass via Unrelated RRset


- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 8 Nov 2026
- **Updated:** 10 Nov 2026
- **Also known as:** AZL-113218, DEBIAN-CVE-2026-123581, GHSA-6w9h-68h2-v6xq, GHSA-929p-gjf6-5hqj, RUSTSEC-2026-0512, RUSTSEC-2026-0520, UBUNTU-CVE-2026-123581

## What is CVE-2026-123581?

CVE-2026-123581 is a medium-severity vulnerability in hickory-dns, published on 8 Nov 2026. 

### Official description

Hickory DNS hickory-proto through 0.26.0-alpha.1 and hickory-net 0.26.0-beta.1 before 0.26.2 contain a DNSSEC validation flaw that accepts a response as a positive answer when any valid RRset appears in the answer section, without checking that the RRset is responsive to the query. Attackers can supply signed but unrelated RRsets so that responses lacking matching records are validated as positive answers instead of as no-data responses.

Weakness: CWE-345 (Insufficient Verification of Data Authenticity)

## Which versions are affected by CVE-2026-123581?

2 open source packages ship an affected version, including hickory-net and hickory-proto.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `hickory-net` | crates.io | From 0.0.0-0 | 0.26.2 |
| `hickory-proto` | crates.io | From 0.0.0-0 | 0.26.0-beta.1 |

## How do I fix CVE-2026-123581?

Upgrade hickory-net to 0.26.2 or later.

## Is CVE-2026-123581 being exploited?

There is no known exploitation of CVE-2026-123581 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-123581 and fix it if it is affected.

What it is: CVE-2026-123581 is a medium-severity vulnerability in hickory-dns, published on 8 Nov 2026. 
Exploitation: There is no known exploitation of CVE-2026-123581 in the wild and no public exploit code.

Affected packages and fixed versions:
- hickory-net (crates.io): affected from 0.0.0-0; fixed in 0.26.2
- hickory-proto (crates.io): affected from 0.0.0-0; fixed in 0.26.0-beta.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-123581/ (Markdown: https://insights.sbomify.com/CVE-2026-123581/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-123581
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-123581
- OSV: https://osv.dev/vulnerability/CVE-2026-123581

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-123581/
Summaries are generated and may contain mistakes; the official description above is the record.