CVE-2026-33558 (GCVE-0-2026-33558)
Vulnerability from cvelistv5 – Published: 2026-04-20 13:20 – Updated: 2026-04-20 14:20
VLAI
EPSS
VEX
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
5.3 (Medium)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-20 14:20 UTC
CWE
- CWE-533 - DEPRECATED: Information Exposure Through Server Log Files
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://kafka.apache.org/cve-list | vendor-advisory |
| https://lists.apache.org/thread/pz5g4ky3h0k91tfd1… | mailing-list |
| http://www.openwall.com/lists/oss-security/2026/04/17/3 |
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Apache Software Foundation | Apache Kafka |
Affected:
0.11.0 , ≤ 3.9.1
(semver)
Affected: 4.0.0 (semver) |
guessed | |
| Apache Software Foundation | Apache Kafka Clients |
Affected:
0.11.0 , ≤ 3.9.1
(semver)
Affected: 4.0.0 (semver) |
guessed |
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|---|
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.