What is CVE-2026-123578?

CVE-2026-123578 is a low-severity vulnerability in Hickory-Dns, classified under Authentication Bypass by Spoofing. CVSS score: 3.7/10. Published 2026-11-08.

How severe is CVE-2026-123578?

Low severity. CVSS v3 base score is 3.7 out of 10.

Vulnerability in Hickory-Dns

CVE-2026-123578

Hickory DNS hickory-net 0.26.0 before 0.26.2 and hickory-proto 0.25.0 through 0.25.2 skip the check that a UDP response's question section matches the query when the response has an empty question section (QDCOUNT=0), and also skip the case-randomization check. Remote attackers able to inject spoofed UDP responses can send QDCOUNT=0 responses to bypass these checks, weakening defenses against DNS spoofing.

Published 2026-11-08.

CVSS v3 metric

CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N.

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

Hickory-Dns

Weakness classification (CWE)

CWE-290 — Authentication Bypass by Spoofing

References

GitHub Security Advisory (GHSA-3w89-7rx5-hpwx) (vendor-advisory)
VulnCheck Advisory: Hickory DNS 0.26.0 before 0.26.2 Response Validation Bypass via QDCOUNT=0 (third-party-advisory)

Frequently asked questions

What is CVE-2026-123578?: CVE-2026-123578 is a low-severity vulnerability in Hickory-Dns, classified under Authentication Bypass by Spoofing. CVSS score: 3.7/10. Published 2026-11-08.
How severe is CVE-2026-123578?: Low severity. CVSS v3 base score is 3.7 out of 10.