Bug 2568721 (CVE-2026-123594) - CVE-2026-123594 hickory-proto: hickory-net: Hickory DNS: Denial of service via improper DNSSEC NSEC validation
Summary: CVE-2026-123594 hickory-proto: hickory-net: Hickory DNS: Denial of service vi...
Keywords:
Status: NEW
Alias: CVE-2026-123594
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-11-08 02:01 UTC by OSIDB Bzimport
Modified: 2026-11-08 02:48 UTC (History)
15 users (show)

Fixed In Version:
Clone Of:
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Description OSIDB Bzimport 2026-11-08 02:01:55 UTC 
Hickory DNS hickory-proto through 0.26.0-alpha.1 and hickory-net 0.26.0-beta.1 before 0.26.2 contain an NSEC validation flaw that returns a secure proof for NXDOMAIN responses when the covering NSEC's Next Domain Name is a strict descendant of the query name, which actually proves the name exists as an empty non-terminal. On-path attackers can flip the unsigned rcode of a genuine signed NODATA response from NOERROR to NXDOMAIN, causing validators to accept forged nonexistence of the name.
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