CVE-2026-10846

Insufficient verification that responses belong to a query

Published Jun 10, 2026 CVSS 4.0 · 8.2 High EPSS < 1% KEV · Not listed
Description
NLnet Labs ldns 1.2.0 up to and including versions 1.9.0, when used in applications as (stub) resolver over UDP, lacks matching the query destination address and port with the response source address and port. Furthermore not the query ID, neither the question of the query is matched with that of the response. This makes applications, that use ldns for (stub) resolver functionality over UDP, vulnerable for off-path poisoning attacks. The drill tool, which is shipped with ldns, suffers from this vulnerability.

Remediation

Vendor Solution

This issue is fixed starting with version 1.9.2.

Tracking

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Advisories

Source ID Title
Ubuntu USN Ubuntu USN USN-8449-1 ldns vulnerability
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Nlnetlabs
Nlnetlabs ldns
Vendors & Products Nlnetlabs
Nlnetlabs ldns
Type Values Removed Values Added
Description NLnet Labs ldns 1.2.0 up to and including versions 1.9.0, when used in applications as (stub) resolver over UDP, lacks matching the query destination address and port with the response source address and port. Furthermore not the query ID, neither the question of the query is matched with that of the response. This makes applications, that use ldns for (stub) resolver functionality over UDP, vulnerable for off-path poisoning attacks. The drill tool, which is shipped with ldns, suffers from this vulnerability.
Title Insufficient verification that responses belong to a query
Weaknesses CWE-346
References
Metrics cvssV4_0

{'score': 8.2, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
NLnet Labs
Published
Updated
Jun 10, 2026, 2:45 PM
Reserved
Jun 4, 2026, 12:06 PM
Status
Analyzed
Published
Jun 10, 2026, 7:16 AM
Modified
Jul 23, 2026, 9:10 AM