Overview
About vulnerability
Summary
Netty’s DnsResolveContext insufficiently validates the bailiwick of NS records, enabling DNS Cache Poisoning. An attacker controlling an authoritative name server for a subdomain can poison the cache for parent domains (like .co.uk).
Details
In io.netty.resolver.dns.DnsResolveContext.AuthoritativeNameServerList#add method accepts any NS record from the AUTHORITY section as long as the record’s name is a suffix of the questionName.
This means if the resolver queries evil.co.uk., it will accept an NS record claiming authority over co.uk.. Subsequently, the handleWithAdditional method caches the associated A records from the ADDITIONAL section directly into the authoritativeDnsServerCache under the parent domain’s key (co.uk.). This bypasses standard bailiwick rules, where a server authoritative for a subdomain should not be trusted to provide authoritative records for its parent. The poisoned cache is then used for all future resolutions under co.uk..
The io.netty.resolver.dns.DnsResolveContext.AuthoritativeNameServerList#cache method only prevents caching if the record is for the root zone (dots == 1).
Impact
DNS Cache Poisoning. Any application using Netty’s DNS resolver is impacted.
Details
- Affected product:
- Apache CXF , Apache Hadoop , Apache Kafka , Apache Log4j , Apache Solr , Apache Spark , Eclipse Jetty , Netty , Spring , Wildfly , artemis , async-http-client , avro , aws-sdk-java , azure-sdk-for-java , bolt-connection-java , camel , cassandra-java-driver , corda , couchbase-jvm-clients , elasticsearch , etcd4j , flink , flink-shaded , grpc-java , infinispan , java-driver , lettuce , logging-flume , neo4j-java-driver , neo4j-ogm , netty , pulsar , rabbitmq-stream-java-client , rsocket-java , tika , vert.x , wildfly , zendesk-java-client , zookeeper
- Affected packages:
- netty-codec-socks @ 4.1.101.Final (+8558 more)