Denial of Service in Hickory-DNS Prior to 0.26.2
CVE-2026-123573

8.7HIGH

Key Information:

Vendor

Hickory-dns

Status
Hickory-dns
Vendor
CVE Published:
8 November 2026

What is CVE-2026-123573?

A denial of service vulnerability exists in Hickory-DNS versions 0.20.1 to prior 0.26.2 that allows attackers to exploit the hickory-proto SVCB and HTTPS record presentation format parser. By supplying untrusted zone files with manipulated service parameter values, attackers can trigger a panic, leading to crashes during the parsing process. This vulnerability can effectively disrupt the service, making it a risk for users relying on Hickory-DNS for DNS operations.

Affected Version(s)

hickory-dns 0.20.1 < 0.26.2

hickory-dns 0.26.2

References

https://github.com/hickory-dns/hickory-dns/security/advis...
vendor-advisory
https://www.vulncheck.com/advisories/hickory-dns-from-0.2...
third-party-advisory

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

kirk-baird
.