Long list of incoming EDNS options degrades performance_CVE-2026-41292

6.6 / 10

MEDIUM

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:U/U:Red

Description

NLnet Labs Unbound up to and including version 1.25.0 is vulnerable to a degradation of service attack related to parsing long lists of incoming EDNS options. An adversary sending queries with too many EDNS options can hold Unbound threads hostage while they are parsing and creating internal data structures for the options. Coordinated attacks can result in degradation and/or denial of service. Unbound 1.25.1 contains a patch with a fix to limit acceptable incoming EDNS options (100).

Basic Information

ID CVE-2026-41292

Source NLnet Labs

Published May 20, 2026 at 09:19

Affected Product

Vendor NLnet Labs

Product Unbound

Affected Versions NLnet Labs Unbound 0

CWE Classification

CWE-407 CWE-770

References

www.nlnetlabs.nl /downloads/unbound/CVE-2026-41292.txt

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    "published": "2026-05-20T09:19:13.022Z",
    "modified": "2026-05-20T09:19:13.022Z",
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