CVE-2026-33558 (GCVE-0-2026-33558)

Vulnerability from cvelistv5 – Published: 2026-04-20 13:20 – Updated: 2026-04-20 14:20
VLAI?
Title
Apache Kafka, Apache Kafka Clients: Information Exposure Through Network Client Log Output
Summary
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.
Severity ?
No CVSS data available.
CWE
  • CWE-533 - DEPRECATED: Information Exposure Through Server Log Files
Assigner
References
Impacted products
Vendor Product Version
Apache Software Foundation Apache Kafka Affected: 0.11.0 , ≤ 3.9.1 (semver)
Affected: 4.0.0 (semver)
Create a notification for this product.
    Apache Software Foundation Apache Kafka Clients Affected: 0.11.0 , ≤ 3.9.1 (semver)
Affected: 4.0.0 (semver)
Create a notification for this product.
Credits
Alyssa Huang <ahuang@confluent.io> Luke Chen <showuon@gmail.com>
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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