CoreDNS has TSIG authentication bypass on DoT, DoH, DoH3, DoQ, and gRPC

Summary CoreDNS' tsig plugin can be bypassed on non-plain-DNS transports because it trusts the transport writer's TsigStatus instead of performing verification itself. In the attached PoC, plain DNS/TCP correctly rejects an invalid TSIG NOTAUTH, while the same invalid-TSIG request is accepted ove...

GHSA-QHMP-Q7XH-99RH CoreDNS has TSIG authentication bypass on DoT, DoH, DoH3, DoQ, and gRPC

Summary CoreDNS' tsig plugin can be bypassed on non-plain-DNS transports because it trusts the transport writer's TsigStatus instead of performing verification itself. In the attached PoC, plain DNS/TCP correctly rejects an invalid TSIG NOTAUTH, while the same invalid-TSIG request is accepted ove...

Allocation of Resources Without Limits or Throttling

Overview Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling through the requestToMsgGet process. An attacker can exhaust CPU and memory resources by sending oversized DNS-over-HTTPS GET requests with large dns query parameters, causing the...

PT-2026-37095

Name of the Vulnerable Software and Affected Versions CoreDNS versions prior to 1.14.3 Description CoreDNS is a DNS server that chains plugins. A denial-of-service issue exists in the DNS-over-HTTPS DoH GET path because it lacks early size validation for requests. A remote, unauthenticated attack...

PT-2026-35932

Name of the Vulnerable Software and Affected Versions CoreDNS versions prior to 1.14.3 Description CoreDNS transport implementations for gRPC, QUIC, DoH, and DoH3 incorrectly handle TSIG Transaction Signature authentication, which is a mechanism used to authenticate DNS messages. In gRPC and QUIC...

SUSE SLED15 / SLES15 Security Update : dnsdist (SUSE-SU-2026:1618-1)

The remote SUSE Linux SLED15 / SLEDSAP15 / SLES15 / SLESSAP15 host has a package installed that is affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:1618-1 advisory. Update to version 1.9.12. - https://www.dnsdist.org/changelog.htmlchange-1.9.12 Security issues fixed: -...

SUSE-SU-2026:1618-1 Security update for dnsdist

This update for dnsdist fixes the following issues: Update to version 1.9.12. - https://www.dnsdist.org/changelog.htmlchange-1.9.12 Security issues fixed: - CVE-2026-0396: crafted DNS queries triggering domain-based dynamic rules can lead to HTML injection in the web dashboard bsc1261236. -...

SUSE CVE-2026-33254

An attacker can create a large number of concurrent DoQ or DoH3 connections, causing unlimited memory allocation in DNSdist and leading to a denial of service. DOQ and DoH3 are disabled by default...

SUSE CVE-2026-33594

A client can trigger excessive memory allocation by generating a lot of queries that are routed to an overloaded DoH backend, causing queries to accumulate into a buffer that will not be released until the end of the connection...

EUVD-2026-24931

A client can trigger excessive memory allocation by generating a lot of queries that are routed to an overloaded DoH backend, causing queries to accumulate into a buffer that will not be released until the end of the connection...

EUVD-2026-24927

An attacker can create a large number of concurrent DoQ or DoH3 connections, causing unlimited memory allocation in DNSdist and leading to a denial of service. DOQ and DoH3 are disabled by default...

CVE-2026-33595

A client can trigger excessive memory allocation by generating a lot of errors responses over a single DoQ and DoH3 connection, as some resources were not properly released until the end of the connection...

CVE-2026-33254

An attacker can create a large number of concurrent DoQ or DoH3 connections, causing unlimited memory allocation in DNSdist and leading to a denial of service. DOQ and DoH3 are disabled by default...

CVE-2026-33594 Outgoing DoH excessive memory allocation

A client can trigger excessive memory allocation by generating a lot of queries that are routed to an overloaded DoH backend, causing queries to accumulate into a buffer that will not be released until the end of the connection...

CVE-2026-33594 Outgoing DoH excessive memory allocation

A client can trigger excessive memory allocation by generating a lot of queries that are routed to an overloaded DoH backend, causing queries to accumulate into a buffer that will not be released until the end of the connection...

CVE-2026-33594

CVE-2026-33594 describes a memory exhaustion issue where a client floods a DoH backend with queries, causing excess memory allocation as queries accumulate in a buffer that is only released at the end of the connection. The connected sources confirm the root cause (buffer growth tied to overloade...

CVE-2026-33594 Outgoing DoH excessive memory allocation

A client can trigger excessive memory allocation by generating a lot of queries that are routed to an overloaded DoH backend, causing queries to accumulate into a buffer that will not be released until the end of the connection...

CVE-2026-33594

A client can trigger excessive memory allocation by generating a lot of queries that are routed to an overloaded DoH backend, causing queries to accumulate into a buffer that will not be released until the end of the connection...

CVE-2026-33595 DoQ/DoH3 excessive memory allocation

A client can trigger excessive memory allocation by generating a lot of errors responses over a single DoQ and DoH3 connection, as some resources were not properly released until the end of the connection...

CVE-2026-33595

The connected documents independently confirm CVE-2026-33595 affects PowerDNS DNSdist, describing a flaw where a client can trigger excessive memory allocation by generating many error responses over a single DoQ/DoH3 connection, with resources not released until connection end. This is the state...