Medium severity · published Apr 26, 2026
CVE-2026-42255
Technitium DNS Server before 15.0 allows DNS traffic amplification via cyclic name server delegation
6.5
CVSS
0.2%
EPSS
No
On KEV
Description
Technitium DNS Server before 15.0 allows DNS traffic amplification via cyclic name server delegation.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 11% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DN
DnsServer · Technitium
before 15.0.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-42255
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-42255
Release Notes
https://github.com/TechnitiumSoftware/DnsServer/blob/master/CHANGELOG.md#technitium-dns-server-change-log
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