Status: UPDATED | Advisory ID: CVE-2026-35554
| CVE | CVE-2026-35554 |
| CVSS Score / Version | 8.7 (High) / CVSS v3.1 |
| Updated | 2026-09-24 |
| CVSS Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N |
| CVSS Prose | attack vector is network; attack complexity is high; privileges required is none; user interaction is none; scope is changed; confidentiality impact is high; integrity impact is high; availability impact is none. |
| Affected products | Apache Kafka |
| Classified as | CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')) |
| Exploitation prediction (EPSS) | 0.65% probability of exploitation in the next 30 days (49% percentile) -- FIRST.org's EPSS model. |
| Vendor | Product | Affected Versions | Patch Status |
|---|---|---|---|
| Apache | Kafka |
| Subsystems | General OT |
| Sectors | Multiple |
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.
Monitor Apache's web page for any future patch releases. See vendor advisory link below.
| Source | Reference |
|---|---|
| NVD | https://nvd.nist.gov/vuln/detail/CVE-2026-35554 |
| CVE | https://www.cve.org/CVERecord?id=CVE-2026-35554 |
| Vendor advisory | https://lists.apache.org/thread/f07x7j8ovyqhjd1to25jsnqbm6wj01d6 |