CVE-2026-115644 — Apache Kafka: Connect Admin REST API Authentication Bypass via Unapplied REST Extensions
Apache Kafka Connect contains an authentication bypass vulnerability affecting the admin REST API when admin.listeners is configured with a separate listener from the main listeners property. When operators isolate the admin REST API by explicitly configuring the "admin.listeners" property, REST extensions specified via rest.extension.classes (such as BasicAuthSecurityRestExtension) are not registered or applied to the admin resource configuration. While the primary REST API listener (configured via listeners) enforces configured authentication and authorization filters, endpoints mounted under the separate admin listener (/admin/loggers) fail to inherit or instantiate these extension filters. As a result, the admin logger endpoint accepts unauthenticated read and write requests even when security extensions are active on the main listener. Impact: An unauthenticated attacker with network access to the admin listener can: 1. Read the complete set of logger names and levels, disclosing loaded class names and which security extensions are in use. 2. Write logger levels, including with scope=cluster which propagates the change to all workers in the Connect cluster. This can be used to suppress logging (setting root to OFF) or generate excessive log output (setting root to TRACE), potentially impacting availability and observability. Mitigation: Users who cannot upgrade immediately can remove the admin.listeners configuration (or leave it unset). When unset, admin resources share the regular listener and inherit its security extensions. Resolution: From Apache Kafka 4.2.2, 4.3.2, and 4.4.0, we make sure the REST extensions specified via "rest.extension.classes" will also apply to "admin.listeners".
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.3% (30-day exploitation probability)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Apache Software Foundation Kafka).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Apache Software Foundation | Kafka | ≥ 2.4.0 and < 4.2.2≥ 4.3.0 and < 4.3.2 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Not enough vector or weakness data: use the affected application’s logs as a starting point.
Timeline
What happened to this CVE, newest first.
- 2026
- Source status changed · Received → Awaiting Analysis
- Record published
- Affected products added · apache software foundation/apache kafka
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 3× References added · Oct 28, 2026 – Oct 29, 2026
- 1× Official description updated · Oct 28, 2026 – Oct 28, 2026
References
4 on the record
Elsewhere on this site
Related CVEs (same products)
- Unknown CVE-2026-83525 Apache Kafka: Incorrect boolean operator in FetchSnapshot RPC handler allows authenticated network clients to crash the KRaft controller via a malformed request. 2d
- Unknown CVE-2026-116593 Apache Kafka: Kafka Connect configuration provider values exposed via validation REST API endpoint 2d
- Unknown CVE-2026-114349 Apache Kafka: Denial of service via unbounded memory allocation when decoding compressed record batches 2d
- Unknown CVE-2026-112375 Apache Kafka: Unauthorized principal can read arbitrary broker files via IncrementalAlterConfigs 2d
- Unknown CVE-2026-111551 Apache Kafka: Denial of service in Kafka Streams and client deserializers via unbounded memory allocation 2d
- Unknown CVE-2026-111496 Apache Kafka: Kafka Streams StreamThread hang from integer overflow in stream-time punctuation 2d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-115644 is "Apache Kafka: Connect Admin REST API Authentication Bypass via Unapplied REST Extensions", rated Unknown. It affects Kafka (Apache Software Foundation); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.26% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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