CVE-2026-42004 — EDNS options smuggling
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…
Published: 2026-06-25 · CVSS: 3.7 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7