Vulnerability · Published Apr 22, 2026 · Assigned by OX

CVE-2026-33258Crafted zones can cause increased resource usage

Medium 5.3

In plain English

A medium-severity resource allocation without limits in Recursor from PowerDNS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 48% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.3Medium
Exploit odds (30 days)0.6%top 51.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

By publishing and querying a crafted zone an attacker can cause allocation of large entries in the negative and aggressive NSEC(3) caches.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Alpine:v3.23pdns-recursor5.3.6-r0ALPINE-CVE-2026-33258
Alpine:v3.24pdns-recursor5.4.1-r0ALPINE-CVE-2026-33258
Debian:12pdns-recursorno fix listedDEBIAN-CVE-2026-33258
Debian:13pdns-recursor5.2.9-0+deb13u1DEBIAN-CVE-2026-33258
Debian:14pdns-recursor5.4.1-1DEBIAN-CVE-2026-33258
Ubuntu:24.04:LTSpdns-recursorno fix listedUBUNTU-CVE-2026-33258
Ubuntu:25.10pdns-recursorno fix listedUBUNTU-CVE-2026-33258
Ubuntu:26.04:LTSpdns-recursorno fix listedUBUNTU-CVE-2026-33258
Ubuntu:26.10pdns-recursorno fix listedUBUNTU-CVE-2026-33258

Affected products (as reported)

VendorProductVersions
PowerDNS Recursor 5.4.0 – before 5.4.15.3.0 – before 5.3.65.2.0 – before 5.2.9

Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References