CVE-2026-35554: Apache Kafka Clients Kafka Producer Message Corruption And Vulnerability

HIGH
Advisory Identifier: GHSA-5qcv-4rpc-jp93
Share
CVSS 8.7
CWE-362
Published
Advisory Summary

CVE-2026-35554 is a HIGH (CVSS 8.7) kafka producer message corruption and vulnerability (CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')) affecting Apache Kafka Clients libraries in the Maven ecosystem. The issue involves kafka producer message corruption and misrouting via buffer pool race condition. Remediation is available by upgrading affected packages to version 3.9.2, 4.0.2, 4.1.2.

CVE-2026-35554 at a Glance

CVE Identifier CVE-2026-35554
GHSA Identifier GHSA-5qcv-4rpc-jp93
Severity HIGH
CVSS v3.1 Base Score 8.7
CWE Classification CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
Affected Product Apache Kafka Clients
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 8.7

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Changed (S:C)
Confidentiality High (C:H)
Integrity High (I:H)
Availability None (A:N)

How to Fix CVE-2026-35554

To remediate this vulnerability, upgrade all affected Apache Kafka Clients dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

org.apache.kafka:kafka-clients fixed: 3.9.2 
<dependency>
    <groupId>org.apache.kafka</groupId>
    <artifactId>kafka-clients</artifactId>
    <version>3.9.2</version>
</dependency>
org.apache.kafka:kafka-clients fixed: 4.0.2 
<dependency>
    <groupId>org.apache.kafka</groupId>
    <artifactId>kafka-clients</artifactId>
    <version>4.0.2</version>
</dependency>
org.apache.kafka:kafka-clients fixed: 4.1.2 
<dependency>
    <groupId>org.apache.kafka</groupId>
    <artifactId>kafka-clients</artifactId>
    <version>4.1.2</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree -Dincludes=org.apache.kafka

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-35554, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.apache.kafka

Analyze the terminal output to locate any version of Apache Kafka Clients in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.9.2), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.apache.kafka command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition'), where the product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently. In Apache Kafka Clients, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

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.

CVE-2026-35554 Affected Apache Kafka Clients Versions

3 component(s)
Fixed Versions:
3.9.24.0.24.1.2
Product / Package Ecosystem Affected Versions Fixed Version
org.apache.kafka:kafka-clients
maven/org.apache.kafka/kafka-clients
Maven
≥ 2.8.0
< 3.9.2
3.9.2
org.apache.kafka:kafka-clients
maven/org.apache.kafka/kafka-clients
Maven
≥ 4.0.0
< 4.0.2
4.0.2
org.apache.kafka:kafka-clients
maven/org.apache.kafka/kafka-clients
Maven
≥ 4.1.0
< 4.1.2
4.1.2

References

NVD — CVE-2026-35554 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-35554
Apache Kafka Clients Source Repository REPOSITORY
https://github.com/apache/kafka/pull/21065
Apache Kafka Clients Source Repository REPOSITORY
https://github.com/apache/kafka/pull/21285
Apache Kafka Clients Source Repository REPOSITORY
https://github.com/apache/kafka/pull/21286
Apache Kafka Clients Source Repository REPOSITORY
https://github.com/apache/kafka/pull/21287
Apache Kafka Clients Source Repository REPOSITORY
https://github.com/apache/kafka/pull/21288
Security Fix Commit FIX COMMIT
https://github.com/apache/kafka/commit/1df2ac5b2ba4d1b5ed54b895ff6fb9539303ccb5
Apache Kafka Clients Source Repository REPOSITORY
https://github.com/apache/kafka
issues.apache.org/jira/browse/kafka-1... WEB
https://issues.apache.org/jira/browse/KAFKA-19012
lists.apache.org/thread/f07x7j8ovyqh... WEB
https://lists.apache.org/thread/f07x7j8ovyqhjd1to25jsnqbm6wj01d6
Apache Kafka Clients Security Information SECURITY
http://www.openwall.com/lists/oss-security/2026/04/07/6

Frequently Asked Questions

What is CVE-2026-35554?
CVE-2026-35554 is a security vulnerability in Apache Kafka Clients involving Kafka Producer Message Corruption and Misrouting via Buffer Pool Race Condition under CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition').
Which Apache Kafka Clients versions are affected?
Affected versions include releases prior to 3.9.2, 4.0.2, 4.1.2 across affected packages: org.apache.kafka:kafka-clients.
What version fixes CVE-2026-35554?
Upgrading to 3.9.2, 4.0.2, 4.1.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is kafka-clients affected?
Yes, org.apache.kafka:kafka-clients is affected in releases prior to 3.9.2, 4.0.2, 4.1.2. Upgrade your dependency to 3.9.2, 4.0.2, 4.1.2 or later.
What is the CVSS score of CVE-2026-35554?
CVE-2026-35554 has a CVSS v3.1 base score of 8.7 (HIGH) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N.
What CWE is associated with CVE-2026-35554?
CVE-2026-35554 is classified under CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') (The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.).
How can I check Maven dependencies for CVE-2026-35554?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.apache.kafka'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-5qcv-4rpc-jp93",
  "modified" : "2026-04-13T19:22:21Z",
  "published" : "2026-04-07T15:30:50Z",
  "aliases" : [ "CVE-2026-35554" ],
  "summary" : "Apache Kafka Clients: Kafka Producer Message Corruption and Misrouting via Buffer Pool Race Condition",
  "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.\n\nWhen 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.\n\n\nData Confidentiality:\nMessages 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.\n\nData Integrity:\nConsumers on the receiving topic may encounter unexpected or incompatible messages, leading to deserialization failures, processing errors, and corrupted downstream data.\n\nThis issue affects Apache Kafka versions ≤ 3.9.1, ≤ 4.0.1, and  ≤ 4.1.1.\n\nKafka 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" : [ {
    "type" : "CVSS_V3",
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  }, {
    "type" : "WEB",
    "url" : "https://github.com/apache/kafka/pull/21285"
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    "type" : "WEB",
    "url" : "https://github.com/apache/kafka/pull/21286"
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    "url" : "http://www.openwall.com/lists/oss-security/2026/04/07/6"
  } ],
  "database_specific" : {
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    "nvd_published_at" : "2026-04-07T14:16:23Z"
  }
}