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CVE-2026-42387

Insufficient input validation in ZoneToCache

Published: Jun 25, 2026Updated: Jun 25, 2026 Sources: CVE List NVDCWE-20
5.9MEDIUM
NVD MITRE
EPSS Score
0.4%
Top 68.6%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
No Fix Available
Self-Check
OpenVAS

Description

A malicious authoritative server can send a crafted zone via the ZoneToCache function that leads to a crash of the Recursor due to insuffcient input validation.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-20

Affected Products

PowerDNS
oss-project·DKaka dnsdist, powerdns recursor, powerdns authoritative
RecursorOn-premNetwork Device
Networking Infrastructure / dns-dhcp-ntp

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Initial Access
View detailed technique mapping

References

https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-powerdns-2026-08.html
docs.powerdns.com

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