CVE-2026-33558
Apache Kafka exposes sensitive information in its DEBUG logs
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. Apache advises Kafka users to upgrade to v3.9.2, v4.0.1, or later to avoid this vulnerability.
How to fix CVE-2026-33558
To remediate CVE-2026-33558, upgrade the affected package to a fixed version below.
- —upgrade to 3.9.2 or later
- —upgrade to 3.9.2 or later
Is CVE-2026-33558 being exploited?
Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- >= 0.11.0, < 3.9.2, >= 4.0.0, < 4.0.1
- >= 0.11.0, < 3.9.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |