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).
Affected products
nlnetlabs: unbound
References9
- www.nlnetlabs.nl/downloads/unbound/CVE-2026-41292.txt MitigationVendor Advisory
- access.redhat.com/errata/RHSA-2026:24013
- access.redhat.com/errata/RHSA-2026:36320
- access.redhat.com/errata/RHSA-2026:36777
- access.redhat.com/errata/RHSA-2026:37282
- access.redhat.com/errata/RHSA-2026:54769
- access.redhat.com/security/cve/CVE-2026-41292
- bugzilla.redhat.com/show_bug.cgi?id=2480125
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-41292…
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
6.6
MEDIUM
Score source: CNA
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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Red - EPSS — exploit probability
- 1% percentile: 55 · as of 14 November 2026
- CWE
- CWE-407CWE-770CWE-1050
Could this be exploited in your environment?
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