---
id: "CVE-2026-123573"
page: "https://infrastack.ai/live/CVE-2026-123573"
kind: "vulnerability"
aliases: ["CVE-2026-123573"]
title: "hickory-dns: crafted zone file crashes DNS parser via SVCB records"
severity: "high"
cvss: 8.7
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["dns", "hickory-dns", "hickory-proto", "package", "rust"]
not_affected_if: ["no-svcb-https-parsing", "trusted-zone-files-only"]
published_at: "2026-11-08T02:16:50+00:00"
first_seen_at: "2026-11-08T02:21:12+00:00"
updated_at: "2026-11-08T02:22:56+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-123573", "first_seen_at": "2026-11-08T02:21:12+00:00"}]
exploit_sources: []
---

# hickory-dns: crafted zone file crashes DNS parser via SVCB records

Link for people: https://infrastack.ai/live/CVE-2026-123573 (this .md is for agents)

hickory-dns, a Rust DNS library and server, panics while parsing SVCB and HTTPS record presentation formats when a service parameter value is malformed by a stray quote. An attacker who can supply an untrusted zone file can crash the parsing process, causing a denial of service.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the hickory-dns version in your Cargo.lock or dependency tree, e.g. `cargo tree -i hickory-proto`
- Confirm whether your application parses untrusted zone files containing SVCB or HTTPS records
- Versions `0.20.1` through below `0.26.2` are in the affected range

## Fix

- Move hickory-dns to `0.26.2` or later

## Timeline

- 2026-11-08T02:21:12+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-123573

## Documents

- [advisory] Vendor advisory: github.com https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-wgfr-mphw-j5g4
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/hickory-dns-from-0.20.1-before-0.26.2-panic-in-svcb-https-zone-file-parser

## From the sources

hickory-dns from 0.20.1 before 0.26.2 contains a denial of service vulnerability in the hickory-proto SVCB and HTTPS record presentation format parser. Attackers can supply untrusted zone files where only a single or double quote replaces a service parameter value, triggering a panic that crashes the parsing process.

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