Technitium DnsServer up to 14.x Cyclic Name Server Delegation incorrect provision of specified functionality

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Technitium DnsServer up to 14.x. Affected by this vulnerability is an unknown functionality of the component Cyclic Name Server Delegation. The manipulation results in incorrect provision of specified functionality. This vulnerability is cataloged as CVE-2026-42255. The attack may be launched remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Technitium DnsServer up to 14.x. Affected is some unknown functionality of the component Cyclic Name Server Delegation. The manipulation with an unknown input leads to a incorrect provision of specified functionality vulnerability. CWE is classifying the issue as CWE-684. The code does not function according to its published specifications, potentially leading to incorrect usage. This is going to have an impact on integrity, and availability. CVE summarizes:

Technitium DNS Server before 15.0 allows DNS traffic amplification via cyclic name server delegation.

The advisory is available at github.com. This vulnerability is traded as CVE-2026-42255 since 04/26/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available.

Upgrading to version 15.0.0 eliminates this vulnerability. The upgrade is hosted for download at github.com.

The vulnerability is also documented in the vulnerability database at CNNVD (CNNVD-202604-5132). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.7

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.2
CNA Vector (MITRE): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Incorrect provision of specified functionality
CWE: CWE-684
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: DnsServer 15.0.0

Timelineinfo

04/26/2026 Advisory disclosed
04/26/2026 +0 days CVE reserved
04/26/2026 +0 days VulDB entry created
04/28/2026 +2 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-42255 (🔒)
GCVE (CVE): GCVE-0-2026-42255
GCVE (VulDB): GCVE-100-359634
CNNVD: CNNVD-202604-5132 - Technitium DNS Server 安全漏洞

Entryinfo

Created: 04/26/2026 09:03
Updated: 04/28/2026 12:10
Changes: 04/26/2026 09:03 (64), 04/27/2026 23:21 (6), 04/28/2026 12:10 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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