nvd.nist.gov
https://nvd.nist.gov/vuln/detail/CVE-2026-42004 CVE-2026-42004
LOW
PowerDNS DNSdist EDNS Options Smuggling Vulnerability
Record summary
CVE-2026-42004 has a selected CVSS score of 3.7 (low).
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.
Description source: CVE List
Exploitation context
CISA SSVC decision
ExploitationNone
AutomatableNo
Technical impactPartial
CISA Coordinator · SSVC 2.0.3 · Evaluated Jun 25, 2026 · Source: CVE List
Affected products and versions
1| Product | Source | Version range | Status |
|---|---|---|---|
DNSdistBrowse PowerDNS / DNSdistDefault status: unaffected | CVE List | 1.9.0 to < 1.9.15 | affected |
| 2.0.0 to < 2.0.7 | affected |
References
2dnsdist.org
https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html