What’s Vulnerable › Vulnerabilities
CVE-2026-42004: EDNS options smuggling
- Severity: low (CVSS 3.7 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-06-25 · updated 2026-10-25
- Weakness: CWE-115
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.
Affected products
- PowerDNS DNSdist: from 1.9.0 before 1.9.15; from 2.0.0 before 2.0.7 — fixed in 1.9.15, 2.0.7
How to fix
Upgrade to a fixed version: PowerDNS DNSdist 1.9.15, 2.0.7. Check the vendor advisory for mitigations.
References
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