Description
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. We advise the Kafka users to upgrade to v3.9.2, v4.0.1, or later to avoid this vulnerability.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Apache Software Foundation | Apache Kafka | 0.11.0 – ≤ 3.9.1, 4.0.0 | — |
| Apache Software Foundation | Apache Kafka Clients | 0.11.0 – ≤ 3.9.1, 4.0.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | kafka | No fix yet | — |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | druid | 36.0.0-r15 | — |
| Wolfi rolling | strimzi-kafka-operator-kafka-thirdparty-libs-cc | 0.51.0-r24 | — |
| Wolfi rolling | wildfly-openjdk-17 +1 | 40.0.0-r0 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.apache.kafka:kafka-clients | >= 0.11.0, < 3.9.2 | 3.9.2 | GHSA-wf66-mphr-4c4r |
| Maven | org.apache.kafka:kafka-clients | >= 4.0.0, < 4.0.1 | 4.0.1 | GHSA-wf66-mphr-4c4r |
Advisories 2
- WID-SEC-2026-3043 IBM QRadar SIEM: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 17, 2026
- WID-SEC-2026-1166 Apache Kafka: Mehrere Schwachstellen BSI CERT-Bund (WID) · Aug 13, 2026
References
- https://kafka.apache.org/cve-list vendor-advisory
- https://lists.apache.org/thread/pz5g4ky3h0k91tfd14p0dzqjp80960kl mailing-list