Powerdns Recursor vulnerabilities

CVE-2026-52688 High · 7.5 CWE-295 Jul 23, 2026

RRSIGs with too few labels can lead to bypass of DNSSEC wildcard validation

CVE-2026-52686 Low · 3.7 CWE-347 Jul 23, 2026

Wildcard CNAME proof validation bypass

The issue is a DNSSEC validation bypass where wildcard expansion proofs (NSEC/NSEC3 records) are accepted without signature validation when the wildcard answer is a CNAME or DNAME record.

CVE-2026-52684 Low · 3.7 Jul 23, 2026

Prefetch Feature Allows Persistent Ghost Domain Cache Poisoning Attack

If the auth responds very slowly and the records expire in between, the capping of TTLs is not enforced for lack of data. This does not happen on regular resolve as then then the child records are used immediately if not expired and thus valid, or the records are expired, and in that case not used. So this case can only happen if almost expired records are used to refresh the authoritative NS records.

CVE-2026-52690 Medium · 5.9 CWE-290 Jun 25, 2026

Spoofed answers can mark an authoritative non-EDNS capable

Spoofing replies to Recursor might mark an IP of an authoritative server as not supporting EDNS, causing valdiation of DNSSEC records served by that server to fail.

CVE-2026-42390 Medium · 5.3 CWE-20 Jun 25, 2026

ZONEMD validation can be bypassed

An invalid zone might pass ZONEMD validation while it should not. This is only relevant if ZoneToCache is configured with ZONEMD validation.

CVE-2026-42389 Medium · 5.3 CWE-20 Jun 25, 2026

Reject more queries with invalid header values

This fix provides extra hardening for the 5.4.x branch by doing extra validation of incoming answers from authoritative servers.

CVE-2026-42388 Medium · 5.9 CWE-20 Jun 25, 2026

Missing input validation for catalog zones

Incomplete validation of the SOA record present in a catalog zone might lead to a crash.

CVE-2026-42387 Medium · 5.9 CWE-20 Jun 25, 2026

Insufficient input validation in ZoneToCache

A malicious authoritative server can send a crafted zone via the ZoneToCache function that leads to a crash of the Recursor due to insuffcient input validation.

CVE-2026-40012 Medium · 5.3 CWE-524 Jun 25, 2026

Information about ECS zero scoped answers might leak to clients that use a specific ECS

ECS zero scoped answers are stored in the packet cache while they should not. This impacts only configurations that have ECS enabled;

CVE-2026-33612 High · 7.5 CWE-349 Jun 25, 2026

ZoneToCache can poison the cache

A malicious authoritative server can send a crafted zone via the ZoneToCache function that leads to cache poisoning.

CVE-2026-33601 Medium · 4.9 CWE-476 Apr 22, 2026

Insufficient validation of zonemd record

If you use the zoneToCache function with a malicious authoritative server, an attacker can send a zone that result in a null pointer dereference, caused by a missing consistency check and leading to a denial of service.

CVE-2026-33600 Medium · 4.9 CWE-476 Apr 22, 2026

Null pointer dereference in RPZ transfer

An RPZ sent by a malicious authoritative server can result in a null pointer dereference, caused by a missing consistency check and leading to a denial of service.

CVE-2026-33262 Medium · 5.9 CWE-476 Apr 22, 2026

Insufficient validation of cookie reply

An attacker can send replies that result in a null pointer dereference, caused by a missing consistency check and leading to a denial of service. Cookies are disabled by default.

CVE-2026-33261 Medium · 5.9 CWE-353 Apr 22, 2026

Null pointer accces in aggressive NSEC(3) cache

A zone transition from NSEC to NSEC3 might trigger an internal inconsistency and cause a denial of service.

CVE-2026-33260 High · 7.5 CWE-770 Apr 22, 2026

Insufficient input validation of internal webserver

An attacker can send a web request that causes unlimited memory allocation in the internal web server, leading to a denial of service. The internal web server is disabled by default.

CVE-2026-33259 Medium · 5.0 CWE-416 Apr 22, 2026

Concurrent modification of RPZ data can lead to denial of servce

Having many concurrent transfers of the same RPZ can lead to inconsistent RPZ data, use after free and/or a crash of the recursor. Normally concurrent transfers of the same RPZ zone can only occur with a malfunctioning RPZ provider.

CVE-2026-33258 High · 7.5 CWE-770 Apr 22, 2026

Crafted zones can cause increased resource usage

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

CVE-2026-33257 High · 7.5 CWE-770 Apr 22, 2026

Insufficient input validation of internal webserver

An attacker can send a web request that causes unlimited memory allocation in the internal web server, leading to a denial of service. The internal web server is disabled by default.

CVE-2026-33256 High · 7.5 CWE-770 Apr 22, 2026

Unbounded memory allocation by internal web server

An attacker can send a web request that causes unlimited memory allocation in the internal web server, leading to a denial of service. The internal web server is disabled by default.

CVE-2026-24027 Medium · 5.3 CWE-294 Feb 9, 2026

Crafted zones can lead to increased incoming network traffic

Crafted zones can lead to increased incoming network traffic.

CVE-2026-0398 Medium · 5.3 CWE-770 Feb 9, 2026

Crafted zones can lead to increased resource usage and crafted CNAME chains can lead to cache poisoning in Recursor

Crafted zones can lead to increased resource usage and crafted CNAME chains can lead to cache poisoning in Recursor.

CVE-2025-59024 Medium · 6.5 CWE-345 Feb 9, 2026

Crafted delegations or IP fragments can poison cached delegations in Recursor

Crafted delegations or IP fragments can poison cached delegations in Recursor.

CVE-2025-59023 High · 8.2 CWE-294 Feb 9, 2026

Crafted delegations or IP fragments can poison cached delegations in Recursor

Crafted delegations or IP fragments can poison cached delegations in Recursor.

CVE-2025-59030 High · 7.5 CWE-276 Dec 9, 2025

Insufficient validation of incoming notifies over TCP can lead to a denial of service in Recursor

An attacker can trigger the removal of cached records by sending a NOTIFY query over TCP.

CVE-2025-59029 Medium · 5.3 CWE-617 Dec 9, 2025

Internal logic flaw in cache management can lead to a denial of service in PowerDNS Recursor

An attacker can trigger an assertion failure by requesting crafted DNS records, waiting for them to be inserted into the records cache, then send a query with qtype set to ANY.