Apache Kafka Clients: Kafka Producer Message Corruption and Misrouting via Buffer Pool Race Condition
Summary
| CVE | CVE-2026-35554 |
|---|---|
| State | PUBLISHED |
| Assigner | apache |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-04-07 14:16:23 UTC |
| Updated | 2026-04-07 17:16:32 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v3.1 8.7 HIGH from ADP
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
Problem Types: CWE-362 | CWE-416 | CWE-416 CWE-416 Use After Free | CWE-362 CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 8.7 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 8.7 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
NoneUser Interaction
NoneScope
ChangedConfidentiality
HighIntegrity
HighAvailability
NoneCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Apache Software Foundation | Apache Kafka Clients | affected 2.8.0 3.9.1 semver | Not specified |
| CNA | Apache Software Foundation | Apache Kafka Clients | affected 4.0.0 4.0.1 semver | Not specified |
| CNA | Apache Software Foundation | Apache Kafka Clients | affected 4.1.0 4.1.1 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| issues.apache.org/jira/browse/KAFKA-19012 | [email protected] | issues.apache.org | |
| www.openwall.com/lists/oss-security/2026/04/07/6 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | |
| lists.apache.org/thread/f07x7j8ovyqhjd1to25jsnqbm6wj01d6 | [email protected] | lists.apache.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Bharath Vissapragada <[email protected]> (en)
CNA: Donny Nadolny <[email protected]> (en)
CNA: Donny Nadolny <[email protected]> (en)
There are currently no legacy QID mappings associated with this CVE.