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
https://access.redhat.com/errata/RHSA-2026:24013
https://access.redhat.com/errata/RHSA-2026:36320
https://access.redhat.com/errata/RHSA-2026:36777
https://access.redhat.com/errata/RHSA-2026:37282
https://access.redhat.com/errata/RHSA-2026:54769
https://access.redhat.com/security/cve/CVE-2026-41292
https://bugzilla.redhat.com/show_bug.cgi?id=2480125
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-41292.json

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-05-20 10:16

Updated : 2026-08-26 13:18

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

CWE-1050

Excessive Platform Resource Consumption within a Loop

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"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2480125", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-41292.json", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "sep@nlnetlabs.nl", "description": [{"lang": "en", "value": "CWE-407"}, {"lang": "en", "value": "CWE-770"}]}, {"type": "Secondary", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "description": [{"lang": "en", "value": "CWE-1050"}]}], "descriptions": [{"lang": "en", "value": "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)."}, {"lang": "es", "value": "NLnet Labs Unbound hasta e incluyendo la versi\u00f3n 1.25.0 es vulnerable a un ataque de degradaci\u00f3n de servicio relacionado con el an\u00e1lisis de largas listas de opciones EDNS entrantes. Un adversario que env\u00ede consultas con demasiadas opciones EDNS puede mantener los hilos de Unbound como rehenes mientras estos analizan y crean estructuras de datos internas para las opciones. Los ataques coordinados pueden resultar en degradaci\u00f3n y/o denegaci\u00f3n de servicio. Unbound 1.25.1 contiene un parche con una soluci\u00f3n para limitar las opciones EDNS entrantes aceptables (100)."}], "lastModified": "2026-08-26T13:18:46.237", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:nlnetlabs:unbound:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "45EC9AEF-23EC-4ECC-A769-18DF07B2CAEC", "versionEndExcluding": "1.25.1"}], "operator": "OR"}]}], "sourceIdentifier": "sep@nlnetlabs.nl"}