CVE-2026-33558

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://kafka.apache.org/cve-list	Vendor Advisory
https://lists.apache.org/thread/pz5g4ky3h0k91tfd14p0dzqjp80960kl	Mitigation Vendor Advisory
http://www.openwall.com/lists/oss-security/2026/04/17/3	Mailing List

Configurations

Configuration 1 (hide)

OR	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::::::

History

No history.

Information

Published : 2026-04-20 14:16

Updated : 2026-06-17 10:37

NVD link : CVE-2026-33558

Mitre link : CVE-2026-33558

CVE.ORG link : CVE-2026-33558

JSON object : View

Products Affected

apache

kafka

CWE

CWE-533

DEPRECATED: Information Exposure Through Server Log Files

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