CVE-2026-50045

EUVD-2026-47671
In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, a single client query for a deeply nested name under a DNSSEC-signed parent can cause Unbound to send more upstream packets per client query than the configured 'max-global-quota'. This effectively bypasses a security configuration that limits upstream amplification traffic.
Network Amplification
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
5.3 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Base Score
CVSS 3.x
EPSS Score
Percentile: 19.91%
Affected Products (NVD)
VendorProductVersion
nlnetlabsunbound
1.22.0 ≤
𝑥
< 1.25.2
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
unbound
bookworm
vulnerable
bookworm (security)
vulnerable
forky
1.26.0-2
fixed
sid
1.26.0-2
fixed
trixie
vulnerable
trixie (security)
vulnerable
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
unbound
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
resolute
needs-triage
trusty
needs-triage
xenial
needs-triage
Azure Linux logo
Azure Linux Releases
Azure Package
Release
unbound
Azure Linux 3.0
0:1.25.2-1.azl3
fixed
Common Weakness Enumeration
References
https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-50045.txt