CVE-2025-27818

/// Technical description

A possible security vulnerability has been identified in Apache Kafka.

This requires access to a alterConfig to the cluster resource, or Kafka Connect worker, and the ability to create/modify connectors on it with an arbitrary Kafka client SASL JAAS config

and a SASL-based security protocol, which has been possible on Kafka clusters since Apache Kafka 2.0.0 (Kafka Connect 2.3.0).

When configuring the broker via config file or AlterConfig command, or connector via the Kafka Kafka Connect REST API, an authenticated operator can set the `sasl.jaas.config`

property for any of the connector's Kafka clients to "com.sun.security.auth.module.LdapLoginModule", which can be done via the

`producer.override.sasl.jaas.config`, `consumer.override.sasl.jaas.config`, or `admin.override.sasl.jaas.config` properties.

This will allow the server to connect to the attacker's LDAP server

and deserialize the LDAP response, which the attacker can use to execute java deserialization gadget chains on the Kafka

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References