CVE-2026-42004

Description

An attacker can send a crafted EDNS OPT record that will be ignored by DNSdist’s filtering rules, but will be rewritten as a valid OPT record when EDNS Client Subnet is inserted, causing the backend to see the EDNS option(s) that DNSdist did not filter.

CVSS Vector

References

• https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html