CVE-2026-33558 json
Apache Kafka, Apache Kafka Clients: Information Exposure Through Network Client Log Output
published 6mo ago modified 14d ago also BIT-kafka-2026-33558 , EUVD-2026-23849 , GHSA-wf66-mphr-4c4r
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 50%
- public exploits
- 0
- none known
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.
Patch / fix
- maven org.apache.kafka:kafka-clients 3.9.2, 4.0.1
- bitnami kafka 3.9.2, 4.0.1
- apache kafka 3.9.2, 4.0.1
- org.apache.kafka kafka 3.9.2, 4.0.1
- org.apache.kafka kafka-clients 3.9.2, 4.0.1
Is CVE-2026-33558 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 6mo ago
Exploit prediction
0.63% chance of exploitation in the next 30 days, higher than 50% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
| GitHub | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
| OSV | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| maven | org.apache.kafka:kafka-clients | >=0.11.0, <3.9.2 >=4.0.0, <4.0.1 |
3.9.2 4.0.1 |
| bitnami | kafka | >=0.11.0, <3.9.2 >=4.0.0, <4.0.1 |
3.9.2 4.0.1 |
Affected products
- Apache Software Foundation Apache Kafka
- Apache Software Foundation Apache Kafka Clients
Classification
References
-
kafka.apache.org
/cve-list
vendor-advisory, web, advisory
-
lists.apache.org
/thread/pz5g4ky3h0k91tfd14p0dzqjp80960kl
mailing-list, web, mitigation, vendor-advisory, advisory
-
openwall.com
/lists/oss-security/2026/04/17/3
web, mailing-list, discussion
-
nvd.nist.gov
/vuln/detail/CVE-2026-33558
advisory, web
-
github.com
/apache/kafka
package
Sources
- CVE List CVE-2026-33558
- GitHub Advisory GHSA-wf66-mphr-4c4r
- NVD CVE-2026-33558
- OSV BIT-kafka-2026-33558
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.