In Spring for Apache Kafka, overly broad trusted-package matching in header mappers exposes JDK classes to deserialization

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

8.1 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

• CVE-2026-41731: 0.51% estimated exploitation activity in the next 30 days; percentile 43.54 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

JsonKafkaHeaderMapper and the deprecated DefaultKafkaHeaderMapper matched type headers against trusted packages using a prefix check, meaning that trusting any package implicitly trusted all of its subpackages. Combined with Jackson's default bean deserialization, a producer could supply crafted header values that caused the consumer to deserialize arbitrary JDK types. Affected versions: Spring for Apache Kafka 4.0.0 through 4.0.5; 3.3.0 through 3.3.15; 3.2.0 through 3.2.13; 2.9.0 through 2.9.13; 2.8.0 through 2.8.11.

Published by the source

10 Jun 2026, 00:31 UTC

Last modified by the source

12 Jun 2026, 21:51 UTC

Source last checked

26 Oct 2026, 16:53 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-xq69-5h5v-x9x4

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# Patch Next advisory brief: CVE-2026-41731

Advisory: In Spring for Apache Kafka, overly broad trusted-package matching in header mappers exposes JDK classes to deserialization
IDs: CVE-2026-41731, GHSA-xq69-5h5v-x9x4
Record: https://patchnext.com/advisories/cve-2026-41731 (revision 1, source checked 26 Oct 2026, 16:53 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Partial vendor fix; fixed versions by package: org.springframework.kafka:spring-kafka 4.0.6, 3.3.16. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.springframework.kafka:spring-kafka: affected >= 4.0.0, <= 4.0.5; >= 3.3.0, <= 3.3.15; >= 3.2.0, <= 3.2.13; >= 2.9.0, <= 2.9.13; <= 2.8.11; fixed in 4.0.6, 3.3.16

## Suggested inspection (read-only)
- Maven org.springframework.kafka:spring-kafka: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on org.springframework.kafka:spring-kafka.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-xq69-5h5v-x9x4 (GitHub-reviewed advisory GHSA-xq69-5h5v-x9x4 lists affected ranges: Maven org.springframework.kafka:spring-kafka >=4.0.0 =3.3.0 =3.2.0 =2.9.0 =0 <=2.8.11)

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