PowerDNS Security Advisory 2026-10 for PowerDNS Recursor: Multiple Issues

CVE-2026-52688: RRSIGs with too few labels can lead to bypass of DNSSEC wildcard validation

  • CVE: CVE-2026-52688

  • Date: 2026-07-22T00:00:00+01:00

  • Discovery date: 2026-04-12T00:00:00+01:00

  • Affects: PowerDNS Recursor from up to and including 5.2.11, 5.3.8 and 5.4.3

  • Not affected: PowerDNS Recursor 5.2.12, 5.3.9, 5.4.4

  • Severity: High

  • Impact: DNSSEC Validation bypass

  • Exploit: A crafted reply can bypass DNSSEC validation of wildcards

  • Risk of system compromise: None

  • Solution: Upgrade to patched version

  • CWE: CWE-345

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

  • Last affected: 5.2.11,5.3.8,5.4.3

  • First fixed: 5.2.12,5.3.9,5.4.4

  • Internal ID: 515

  • External Reporter: Qifan Zhang from Palo Alto Networks

A malicious authoritative server can send a crafted reply that leads to DNSSEC wildcard validation bypass.

CVSS Score: 7.5

The remedy is: upgrade to a patched version.

We would like to thank Qifan Zhang from Palo Alto Networks for bringing this issue to our attention.

CVE-2026-62686: Wildcard CNAME proof validation bypass

  • CVE: CVE-2026-52686

  • Date: 2026-07-22T00:00:00+01:00

  • Discovery date: 2026-04-12T00:00:00+01:00

  • Affects: PowerDNS Recursor from up to and including 5.2.11, 5.3.8 and 5.4.3

  • Not affected: PowerDNS Recursor 5.2.12, 5.3.9, 5.4.4

  • Severity: Low

  • Impact: Potential cache poisoning

  • Exploit: A crafted reply from an authoritative server containing specific wildcards

  • Risk of system compromise: None

  • Solution: Upgrade to patched version

  • CWE: CWE-345

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

  • Last affected: 5.2.11,5.3.8,5.4.3

  • First fixed: 5.2.12,5.3.9,5.4.4

  • Internal ID: 518

The NSEC record related to a wildcard proof involving a CNAME is not validated, allowing cache poisoning, but only in very specific cases outside of control of an attacker.

CVSS Score: 3.7

The remedy is: upgrade to a patched version.

We would like to thank Qifan Zhang from Palo Alto Networks for bringing this issue to our attention.