fix(deps): update kafka-client.version to v4.1.2 (release/5.0.x) (patch)

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
org.apache.kafka:kafka_2.13	4.1.1 → 4.1.2
org.apache.kafka:kafka-streams-test-utils	4.1.1 → 4.1.2
org.apache.kafka:kafka-server-common	4.1.1 → 4.1.2
org.apache.kafka:kafka-transaction-coordinator	4.1.1 → 4.1.2
org.apache.kafka:kafka-group-coordinator	4.1.1 → 4.1.2
org.apache.kafka:kafka-raft	4.1.1 → 4.1.2
org.apache.kafka:kafka-metadata	4.1.1 → 4.1.2
org.apache.kafka:kafka-streams	4.1.1 → 4.1.2
org.apache.kafka:kafka-clients	4.1.1 → 4.1.2
org.apache.kafka:kafka-server	4.1.1 → 4.1.2

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Apache Kafka Clients: Kafka Producer Message Corruption and Misrouting via Buffer Pool Race Condition

CVE-2026-35554 / GHSA-5qcv-4rpc-jp93

More information

Details

A race condition in the Apache Kafka Java producer client’s buffer pool management can cause messages to be silently delivered to incorrect topics.

When a produce batch expires due to delivery.timeout.ms while a network request containing that batch is still in flight, the batch’s ByteBuffer is prematurely deallocated and returned to the buffer pool. If a subsequent producer batch—potentially destined for a different topic—reuses this freed buffer before the original network request completes, the buffer contents may become corrupted. This can result in messages being delivered to unintended topics without any error being reported to the producer.

Data Confidentiality:
Messages intended for one topic may be delivered to a different topic, potentially exposing sensitive data to consumers who have access to the destination topic but not the intended source topic.

Data Integrity:
Consumers on the receiving topic may encounter unexpected or incompatible messages, leading to deserialization failures, processing errors, and corrupted downstream data.

This issue affects Apache Kafka versions ≤ 3.9.1, ≤ 4.0.1, and  ≤ 4.1.1.

Kafka users are advised to upgrade to 3.9.2, 4.0.2, 4.1.2, 4.2.0, or later to address this vulnerability.

Severity

• CVSS Score: 8.7 / 10 (High)
• Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

References

• https://nvd.nist.gov/vuln/detail/CVE-2026-35554
• https://issues.apache.org/jira/browse/KAFKA-19012
• https://lists.apache.org/thread/f07x7j8ovyqhjd1to25jsnqbm6wj01d6
• http://www.openwall.com/lists/oss-security/2026/04/07/6
• https://github.com/apache/kafka/pull/21065
• https://github.com/apache/kafka/pull/21285
• https://github.com/apache/kafka/pull/21286
• https://github.com/apache/kafka/pull/21287
• https://github.com/apache/kafka/pull/21288
• https://github.com/apache/kafka/commit/1df2ac5b2ba4d1b5ed54b895ff6fb9539303ccb5
• https://github.com/advisories/GHSA-5qcv-4rpc-jp93

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

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Apache Kafka does not validate JWT tokens in its OAUTHBEARER authentication implementation

CVE-2026-33557 / GHSA-28jg-cgg7-j4wc

More information

Details

A security vulnerability has been identified in Apache Kafka. By default, the broker property sasl.oauthbearer.jwt.validator.class is set to org.apache.kafka.common.security.oauthbearer.DefaultJwtValidator. It accepts any JWT token without validating its signature, issuer, or audience. An attacker can generate a JWT token from any issuer with the preferred_username set to any user, and the broker will accept it.

Apache advises Kafka users using kafka v4.1.0 or v4.1.1 to set the config sasl.oauthbearer.jwt.validator.class to org.apache.kafka.common.security.oauthbearer.BrokerJwtValidator explicitly to avoid this vulnerability. Since Kafka v4.1.2 and v4.2.0 and later, the issue is fixed and will correctly validate the JWT token.

Severity

• CVSS Score: 9.1 / 10 (Critical)
• Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

References

• https://nvd.nist.gov/vuln/detail/CVE-2026-33557
• https://kafka.apache.org/cve-list
• https://lists.apache.org/thread/v57o00hm6yszdpdnvqx2ss4561yh953h
• http://www.openwall.com/lists/oss-security/2026/04/17/2
• https://github.com/apache/kafka/commit/01d8e7db8d08dbd538892b409457ea6bfcc2a422
• https://github.com/advisories/GHSA-28jg-cgg7-j4wc

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

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