FKIE_CVE-2026-41292

Vulnerability from fkie_nvd - Published: 2026-05-20 10:16 - Updated: 2026-05-20 22:49
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
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).
References
sep@nlnetlabs.nlhttps://www.nlnetlabs.nl/downloads/unbound/CVE-2026-41292.txtMitigation, Vendor Advisory
Impacted products
Vendor Product Version
nlnetlabs unbound *
To clipboard 

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      "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)."
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  "id": "CVE-2026-41292",
  "lastModified": "2026-05-20T22:49:46.850",
  "metrics": {
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          "integrityRequirement": "NOT_DEFINED",
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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