CVE-2026-33558
No exploitation reported by the sources we read.
- Published2026-04-20
- Fixed in4.0.1 · 3.9.2
- WeaknessCWE-533
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
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. We advise the Kafka users to upgrade to v3.9.2, v4.0.1, or later to avoid this vulnerability.
Timeline
dates in UTC- 2026-04-2014:16CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-33558?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-33558?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
OSV · NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 4.0 | ≥ 4.0.0, < 4.0.1 | 4.0.1 | OSV |
| 3.9 | ≥ 0.11.0.0, < 3.9.2 | 3.9.2 | NVD |
| 3.9 | ≥ 0.11.0, < 3.9.2 | 3.9.2 | OSV |
| 4.0 | = 4.0.0 | no fix published | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- Update Apache kafka to 4.0.1 · 3.9.2
Advisories and patches
- kafka.apache.orgVendor Advisory
- lists.apache.orgMitigation · Vendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- Published
- 2026-04-20
- Last Modified
- 2026-06-17
- NVD status
- Analyzed
Frequently asked questions
What is CVE-2026-33558?
Is CVE-2026-33558 actively exploited?
What is the CVSS score for CVE-2026-33558?
Running kafka? Hear about its next vulnerability
Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».
No credit card required · No monthly cap on website lookups · 250 API requests/month
Go further
- Following what attackers exploit right now? The CISA KEV additions of the month, with their patch deadlines.
- Running this software? Vulnerability monitoring alerts you to new vulnerabilities in your products.
Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.