CVE-2026-41292

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).

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-41292.txt	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

20 May 2026, 22:49

Type	Values Removed	Values Added
CPE		cpe:2.3:a:nlnetlabs:unbound::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
First Time		Nlnetlabs Nlnetlabs unbound
References	~~() https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-41292.txt -~~	() https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-41292.txt - Mitigation, Vendor Advisory

20 May 2026, 10:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-20 10:16

Updated : 2026-05-20 22:49

NVD link : CVE-2026-41292

Mitre link : CVE-2026-41292

CVE.ORG link : CVE-2026-41292

JSON object : View

Products Affected

nlnetlabs

unbound

CWE

CWE-407

Inefficient Algorithmic Complexity

CWE-770

Allocation of Resources Without Limits or Throttling

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