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TI-2026-25948 Aliases CVE-2026-33558GHSA-wf66-mphr-4c4r

Apache Kafka, Apache Kafka Clients: Information Exposure Through Network Client Log Output

Priority LOW 31CWE-533Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and GitHub. Impact type from CWE-532.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0063 50th percentileScored 2026-11-07
Fix Fixed org.apache.kafka:kafka-clients (Maven): 3.9.2, 4.0.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ApacheApache Kafka0.11.0 – 3.9.1; 4.0.0—No fix listedCNA
ApacheApache Kafka Clients0.11.0 – 3.9.1; 4.0.0—No fix listedCNA
—org.apache.kafka:kafka-clients (Maven)0.11.0 to before 3.9.23.9.2Patch availableGHSA-wf66-mphr-4c4r
—org.apache.kafka:kafka-clients (Maven)4.0.0 to before 4.0.14.0.1Patch availableGHSA-wf66-mphr-4c4r
  • Apache Kafka VendorApache Affected 0.11.0 – 3.9.1; 4.0.0 Fixed in — No fix listed CNA
  • Apache Kafka Clients VendorApache Affected 0.11.0 – 3.9.1; 4.0.0 Fixed in — No fix listed CNA
  • org.apache.kafka:kafka-clients (Maven) Vendor— Affected 0.11.0 to before 3.9.2 Fixed in 3.9.2 Patch available GHSA-wf66-mphr-4c4r
  • org.apache.kafka:kafka-clients (Maven) Vendor— Affected 4.0.0 to before 4.0.1 Fixed in 4.0.1 Patch available GHSA-wf66-mphr-4c4r

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:a:apache:kafka:*:*:*:*:*:*:*:*0.11.0.0 to before 3.9.2VulnerableApache
cpe:2.3:a:apache:kafka:4.0.0:-:*:*:*:*:*:*4.0.0VulnerableApache
cpe:2.3:a:apache:kafka:4.0.0:rc0:*:*:*:*:*:*4.0.0 rc0VulnerableApache
cpe:2.3:a:apache:kafka:4.0.0:rc1:*:*:*:*:*:*4.0.0 rc1VulnerableApache
cpe:2.3:a:apache:kafka:4.0.0:rc3:*:*:*:*:*:*4.0.0 rc3VulnerableApache
  • cpe:2.3:a:apache:kafka:*:*:*:*:*:*:*:* Versions 0.11.0.0 to before 3.9.2 Vulnerable ·Apache
  • cpe:2.3:a:apache:kafka:4.0.0:-:*:*:*:*:*:* Versions 4.0.0 Vulnerable ·Apache
  • cpe:2.3:a:apache:kafka:4.0.0:rc0:*:*:*:*:*:* Versions 4.0.0 rc0 Vulnerable ·Apache
  • cpe:2.3:a:apache:kafka:4.0.0:rc1:*:*:*:*:*:* Versions 4.0.0 rc1 Vulnerable ·Apache
  • cpe:2.3:a:apache:kafka:4.0.0:rc3:*:*:*:*:*:* Versions 4.0.0 rc3 Vulnerable ·Apache

Remediation

  • Fix · GHSA-wf66-mphr-4c4r org.apache.kafka:kafka-clients (Maven) Fixed in 3.9.2 Advisory →
  • Fix · GHSA-wf66-mphr-4c4r org.apache.kafka:kafka-clients (Maven) Fixed in 4.0.1 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33558
  2. 2026-10-03 Alias added: GHSA-wf66-mphr-4c4r
  3. 2026-10-25 EPSS moved to the below the 50th percentile
  4. 2026-10-27 EPSS moved to the 50th–90th percentile

References

Advisory 3

Other 2

  • TI-2025-20589 Apache Kafka Client: Arbitrary file read and SSRF vulnerability CVSS 3.1HIGH 7.5
  • TI-2026-25947 Apache Kafka: Missing JWT token validation in OAUTHBEARER authentication CVSS 3.1CRITICAL 9.1
  • TI-2018-12295 Improper input validation in Apache Kafka CVSS 3.0HIGH 8.8
  • TI-2025-20590 Apache Kafka: Possible RCE attack via SASL JAAS LdapLoginModule configuration CVSS 3.1HIGH 8.8
  • TI-2022-15706 Unauthenticated clients may cause OutOfMemoryError on Apache Kafka Brokers CVSS 3.1HIGH 7.5
  • TI-2025-20591 Apache Kafka: Possible RCE/Denial of service attack via SASL JAAS JndiLoginModule configuration CVSS 3.1HIGH 7.5
See all 16 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences