CVE-2026-33558

Apache Kafka, Apache Kafka Clients: Information Exposure Through Network Client Log Output

Published Apr 20, 2026 CVSS 3.1 · 5.3 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-wf66-mphr-4c4r Apache Kafka exposes sensitive information in its DEBUG logs
History
Type Values Removed Values Added
CPEs cpe:2.3:a:apache:kafka:*:*:*:*:*:*:*:*
cpe:2.3:a:apache:kafka:4.0.0:-:*:*:*:*:*:*
cpe:2.3:a:apache:kafka:4.0.0:rc0:*:*:*:*:*:*
cpe:2.3:a:apache:kafka:4.0.0:rc1:*:*:*:*:*:*
cpe:2.3:a:apache:kafka:4.0.0:rc3:*:*:*:*:*:*
Type Values Removed Values Added
First Time appeared Apache
Apache kafka
Apache kafka Clients
Vendors & Products Apache
Apache kafka
Apache kafka Clients
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title Apache Kafka, Apache Kafka Clients: Information Exposure Through Network Client Log Output
Weaknesses CWE-533
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
apache
Published
Updated
Apr 20, 2026, 2:20 PM
Reserved
Mar 23, 2026, 3:46 AM
Status
Analyzed
Published
Apr 20, 2026, 2:16 PM
Modified
Oct 26, 2026, 9:10 PM