Vulnerability in Hickory-Dns
CVE-2026-123589
The DNS-over-QUIC (DoQ) server in hickory-server (hickory-dns) before 0.26.2 does not apply any timeout when reading a request message from a QUIC stream, bypassing all configured timeouts. A remote unauthenticated client can open a connection and a request stream and hold it open indefinitely, consuming server resources and causing a denial of service.
Published .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.003 (26.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 26.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
The 30-day trend appears once there are two daily scores.
Affected products
References
- github.com/hickory-dns/hickory-dns/security/advisories/GHSA-g8wg-4mwh-fjfv (vendor-advisory)
- www.vulncheck.com/advisories/hickory-dns-before-0.26.2-denial-of-service-via-mi… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-123589?
- CVE-2026-123589 is a medium-severity vulnerability in Hickory-Dns. CVSS score: 5.3/10. Published 2026-11-08.
- How severe is CVE-2026-123589?
- Medium severity. CVSS v3 base score is 5.3 out of 10.