CVE-2026-80225

In NLnetLabs Unbound up to and including 1.26.0, a degradation of service vulnerability is present in the TCP/DoT reading procedure where there is no limit on consecutive reads. A malicious actor that can stream and sustain a rate of distinct uncached names over the TCP/DoT connection, monopolizes a single worker's entire event loop for as long as its writes stay ahead of the drain.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-80225.txt	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nlnetlabs:unbound:*:*:*:*:*:*:*:*

History

23 Sep 2026, 19:57

Type	Values Removed	Values Added
References	~~() https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-80225.txt -~~	() https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-80225.txt - Patch, Vendor Advisory
First Time		Nlnetlabs Nlnetlabs unbound
CPE		cpe:2.3:a:nlnetlabs:unbound::::::::

Information

Published : 2026-09-16 09:17

Updated : 2026-09-23 19:57

NVD link : CVE-2026-80225

Mitre link : CVE-2026-80225

CVE.ORG link : CVE-2026-80225

JSON object : View

Products Affected

nlnetlabs

unbound

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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