Disabled Certificate Validation makes Broker, Proxy Admin Clients vulnerable to MITM attack

Summary

Apache Pulsar Brokers and Proxies create an internal Pulsar Admin Client that does not verify peer TLS certificates, even when tlsAllowInsecureConnection is disabled via configuration. The Pulsar Admin Client's intra-cluster and geo-replication HTTPS connections are vulnerable to man in the middle attacks, which could leak authentication data, configuration data, and any other data sent by these clients. An attacker can only take advantage of this vulnerability by taking control of a machine 'between' the client and the server. The attacker must then actively manipulate traffic to perform the attack. This issue affects Apache Pulsar Broker and Proxy versions 2.7.0 to 2.7.4; 2.8.0 to 2.8.3; 2.9.0 to 2.9.2; 2.10.0; 2.6.4 and earlier.

Timeline

1. Sep 23, 2022, 9:25 AM UTCCVE published
2. May 22, 2025, 3:49 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. May 22, 2025, 6:27 PM UTCRecord last updated

Affected versions

• Apache Software Foundation Apache Pulsar

  From 2.7 · through 2.7.4; From 2.8 · through 2.8.3; From 2.9 · through 2.9.2; through 2.6.4

• org.apache.pulsar:pulsar-brokerMaven

  fixed in 2.7.5

• org.apache.pulsar:pulsar-proxyMaven

  fixed in 2.7.5

• org.apache.pulsar:pulsar-brokerMaven

  From 2.8.0 · fixed in 2.8.4

• org.apache.pulsar:pulsar-proxyMaven

  From 2.8.0 · fixed in 2.8.4

• org.apache.pulsar:pulsar-brokerMaven

  From 2.9.0 · fixed in 2.9.3

• org.apache.pulsar:pulsar-proxyMaven

  From 2.9.0 · fixed in 2.9.3

• org.apache.pulsar:pulsar-brokerMaven

  From 2.10.0 · fixed in 2.10.1

• org.apache.pulsar:pulsar-proxyMaven

  From 2.10.0 · fixed in 2.10.1

References 1