CVE-2026-66374

EUVD-2026-48763
Knot Resolver before 6.4.1 allows remote code execution via a heap-based buffer overflow in the DoQ (DNS-over-QUIC) receive path.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
mitreCNA
8.1 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:L
Base Score
CVSS 3.x
EPSS Score
Percentile: 31%
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
nicknot_resolver
𝑥
< 6.4.1
CNA
Debian logo
Debian Releases
Debian Product
Codename
knot-resolver
bookworm
vulnerable
bookworm (security)
vulnerable
bullseye
vulnerable
forky
vulnerable
sid
6.4.1-1
fixed
trixie
vulnerable
Common Weakness Enumeration
References
https://github.com/venglin/knot-doq
https://openwall.com/lists/oss-security/2026/07/23/6