Improper input validation in Hickory-Dns

CVE-2026-123573

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.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-123573?
CVE-2026-123573 is a high-severity vulnerability in Hickory-Dns, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2026-11-08.
How severe is CVE-2026-123573?
High severity. CVSS v3 base score is 7.5 out of 10.