CVE-2026-41292

HIGH

Unbound <= 1.25.0 - Denial of Service via EDNS Option Parsing

Title source: llm
STIX 2.1

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).

References (1)

Core 1
Core References

Scores

CVSS v3 7.5
EPSS 0.0043
EPSS Percentile 34.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-407 CWE-770
Status published
Products (2)
NLnet Labs/Unbound < 1.25.1
nlnetlabs/unbound < 1.25.1
Published May 20, 2026
Tracked Since May 20, 2026