Apache Kafka Connect Worker deserialization

Summaryinfo

A vulnerability was found in Apache Kafka. It has been rated as critical. The impacted element is an unknown function of the component Connect Worker. This manipulation causes deserialization. This vulnerability is handled as CVE-2023-25194. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Apache Kafka (version unknown). It has been declared as critical. Affected by this vulnerability is an unknown function of the component Connect Worker. The manipulation with an unknown input leads to a deserialization vulnerability. The CWE definition for the vulnerability is CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A possible security vulnerability has been identified in Apache Kafka Connect. This requires access to a 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 Connect clusters since Apache Kafka 2.3.0. When configuring the connector via the 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.JndiLoginModule", 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 connect server. Attacker can cause unrestricted deserialization of untrusted data (or) RCE vulnerability when there are gadgets in the classpath. Since Apache Kafka 3.0.0, users are allowed to specify these properties in connector configurations for Kafka Connect clusters running with out-of-the-box configurations. Before Apache Kafka 3.0.0, users may not specify these properties unless the Kafka Connect cluster has been reconfigured with a connector client override policy that permits them. Since Apache Kafka 3.4.0, we have added a system property ("-Dorg.apache.kafka.disallowed.login.modules") to disable the problematic login modules usage in SASL JAAS configuration. Also by default "com.sun.security.auth.module.JndiLoginModule" is disabled in Apache Kafka 3.4.0. We advise the Kafka Connect users to validate connector configurations and only allow trusted JNDI configurations. Also examine connector dependencies for vulnerable versions and either upgrade their connectors, upgrading that specific dependency, or removing the connectors as options for remediation. Finally, in addition to leveraging the "org.apache.kafka.disallowed.login.modules" system property, Kafka Connect users can also implement their own connector client config override policy, which can be used to control which Kafka client properties can be overridden directly in a connector config and which cannot.

The weakness was released 02/08/2023. This vulnerability is known as CVE-2023-25194 since 02/05/2023. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 01/07/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at CNNVD (CNNVD-202302-515) and CERT Bund (WID-SEC-2023-0300). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• IBM Maximo Asset Management
• IBM Tivoli Netcool/OMNIbus
• IBM Business Automation Workflow
• IBM InfoSphere Data Replication
• IBM QRadar SIEM
• Apache Kafka
• IBM Operational Decision Manager
• IBM App Connect Enterprise
• IBM Integration Bus

Productinfo

Vendor

• Apache

Name

• Kafka

License

• open-source

Website

• Vendor: https://www.apache.org/

CPE 2.3info

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CPE 2.2info

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If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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