High severity · published Aug 25, 2021
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 positive wildcard proof)
7.5
CVSS
1.4%
EPSS
No
On KEV
Description
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).
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.4% · higher than 73% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KR
Knot Resolver · Nic
before 5.3.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-40083
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-40083
Patch
https://gitlab.nic.cz/knot/knot-resolver/-/merge_requests/1169
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