EDNS options smuggling_CVE-2026-42004

3.7 / 10

LOW

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

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.

Basic Information

ID CVE-2026-42004

Source OX

Published Jun 25, 2026 at 12:24

Modified Jun 25, 2026 at 13:44

Affected Product

Vendor PowerDNS

Product DNSdist

Version 1.9.0

Affected Versions PowerDNS DNSdist 1.9.0
PowerDNS DNSdist 2.0.0

CWE Classification

CWE-115

References

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

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    "published": "2026-06-25T12:24:20.140Z",
    "modified": "2026-06-25T13:44:07.962Z",
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