CVE-2026-80225

Medium

Description

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.

SeverityMedium

CVSS5.3

Exploit probability—

ProductNlnetlabs Unbound

PublishedSep 16, 2026

First seenSep 16, 2026

Weakness typeCWE-770Allocation of resources without limits

How to fix

Update

nlnetlabs unbound1.26.1 or later

Vendor advisories

nlnetlabs.nl/downloads/unbound/CVE-2026-80225.txt

Affected products

Product	Affected versions	Fixed in
nlnetlabs unbound	v < 1.26.1	1.26.1

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