CVE-2021-40083: Knot Resolver before 5.3.2 is prone to an assertion failure, triggerable by a remote attacker in an edge case (NSEC3 with too many iterations used for a…

PriorityP338high7.5CVSS 3.1

AVNACLPRNUINSUCNINAH

EPSS

1.42%

69.6th percentile

Knot Resolver before 5.3.2 is prone to an assertion failure, triggerable by a remote attacker in an edge case (NSEC3 with too many iterations used for a positive wildcard proof).

Affected

6 ranges

Vendor	Product	Version range	Fixed in
cz.nic	knot-resolver	>= 0 < 5.3.1-1+deb11u1	5.3.1-1+deb11u1
cz.nic	knot-resolver	>= 0 < 5.4.1-2	5.4.1-2
cz.nic	knot-resolver	>= 0 < 5.4.1-2	5.4.1-2
cz.nic	knot-resolver	>= 0 < 5.4.1-2	5.4.1-2
debian	knot-resolver	< knot-resolver 5.4.1-2 (bookworm)	knot-resolver 5.4.1-2 (bookworm)
nic	knot_resolver	< 5.3.2	5.3.2

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P

osv7.5HIGH

vendor_debian7.5HIGH

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