CVE-2026-42387 PUBLISHED

Insufficient input validation in ZoneToCache

Assigner: OX
Reserved: 27.04.2026 Published: 25.06.2026 Updated: 25.06.2026

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.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 5.9

Attack Vector	Network	Scope	Unchanged
Attack Complexity	High	Confidentiality Impact	None
Privileges Required	None	Integrity Impact	None
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	PowerDNS
Product	Recursor
Versions	Default: unaffected affected from 5.2.0 to 5.2.11 (excl.) affected from 5.3.0 to 5.3.8 (excl.) affected from 5.4.0 to 5.4.3 (excl.)

Credits

nurmukhammyed finder

References

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

Problem Types

Improper Input Validation CWE