Update dependency org.apache.kafka:kafka-clients to v3.9.2 [SECURITY] (master)

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This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
org.apache.kafka:kafka-clients	3.9.0 → 3.9.2

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Apache Kafka Client Arbitrary File Read and Server Side Request Forgery Vulnerability

BIT-kafka-2025-27817 / CVE-2025-27817 / GHSA-vgq5-3255-v292

More information

Details

A possible arbitrary file read and SSRF vulnerability has been identified in Apache Kafka Client. Apache Kafka Clients accept configuration data for setting the SASL/OAUTHBEARER connection with the brokers, including "sasl.oauthbearer.token.endpoint.url" and "sasl.oauthbearer.jwks.endpoint.url". Apache Kafka allows clients to read an arbitrary file and return the content in the error log, or sending requests to an unintended location. In applications where Apache Kafka Clients configurations can be specified by an untrusted party, attackers may use the "sasl.oauthbearer.token.endpoint.url" and "sasl.oauthbearer.jwks.endpoint.url" configuratin to read arbitrary contents of the disk and environment variables or make requests to an unintended location. In particular, this flaw may be used in Apache Kafka Connect to escalate from REST API access to filesystem/environment/URL access, which may be undesirable in certain environments, including SaaS products.

Since Apache Kafka 3.9.1/4.0.0, we have added a system property ("-Dorg.apache.kafka.sasl.oauthbearer.allowed.urls") to set the allowed urls in SASL JAAS configuration. In 3.9.1, it accepts all urls by default for backward compatibility. However in 4.0.0 and newer, the default value is empty list and users have to set the allowed urls explicitly.

Severity

• CVSS Score: 6.2 / 10 (Medium)
• Vector String: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U

References

• https://nvd.nist.gov/vuln/detail/CVE-2025-27817
• https://github.com/apache/kafka
• https://kafka.apache.org/cve-list
• http://www.openwall.com/lists/oss-security/2025/06/09/1

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

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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://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/apache/kafka
• 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

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

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Apache Kafka exposes sensitive information in its DEBUG logs

BIT-kafka-2026-33558 / CVE-2026-33558 / GHSA-wf66-mphr-4c4r

More information

Details

Information exposure vulnerability has been identified in Apache Kafka.

The NetworkClient component will output entire requests and responses information in the DEBUG log level in the logs. By default, the log level is set to INFO level. If the DEBUG level is enabled, the sensitive information will be exposed via the requests and responses output log. The entire lists of impacted requests and responses are:

• AlterConfigsRequest

• AlterUserScramCredentialsRequest

• ExpireDelegationTokenRequest

• IncrementalAlterConfigsRequest

• RenewDelegationTokenRequest

• SaslAuthenticateRequest

• createDelegationTokenResponse

• describeDelegationTokenResponse

• SaslAuthenticateResponse

This issue affects Apache Kafka: from any version supported the listed API above through v3.9.1, v4.0.0. Apache advises Kafka users to upgrade to v3.9.2, v4.0.1, or later to avoid this vulnerability.

Severity

• CVSS Score: 5.3 / 10 (Medium)
• Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

References

• https://nvd.nist.gov/vuln/detail/CVE-2026-33558
• https://github.com/apache/kafka
• https://kafka.apache.org/cve-list
• https://lists.apache.org/thread/pz5g4ky3h0k91tfd14p0dzqjp80960kl
• http://www.openwall.com/lists/oss-security/2026/04/17/3

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

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