Hickory DNS before 0.26.2 DoH Memory Exhaustion via Incomplete Request Bodies

published 2026-09-03 2mo ago modified 2026-11-10 yesterday also EUVD-2026-119334 , GHSA-g5xf-qv55-wv37

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository hickory-dns/hickory-dns. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 35%
public exploits: 0; none known

Hickory DNS before 0.26.2 contains a resource exhaustion vulnerability in its DNS-over-HTTPS HTTP/2 server that lacks sufficient timeouts or limits for incomplete request bodies. Remote attackers can open DoH connections, send incomplete request bodies, and hold connections open to exhaust server memory.

Patch / fix

fixed in 1 distros 1

hickory-dns hickory-dns 0.26.2

rust-hickory-dns Debian 14 0.26.3-1

debian advisories DEBIAN-CVE-2026-123575

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Exploit prediction

0.41% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA	4.0	8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

hickory-dns hickory-dns

Classification

Weakness

CWE-770 Allocation of Resources Without Limits or Throttling

References

github.com /hickory-dns/hickory-dns/security/advisories/GHSA-g5xf-qv55-wv37
vendor-advisory, advisory
vulncheck.com /advisories/hickory-dns-before-0.26.2-doh-memory-exhaustion-via-incomplete-request-bodies
third-party-advisory

Sources

CVE List CVE-2026-123575
NVD CVE-2026-123575
Maintainer advisory GHSA-g5xf-qv55-wv37

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of hickory-dns/hickory-dns published their own advisory on GitHub. Reviewed sources take precedence over it.