CVE-2026-27133: strimzi-kafka-operator · Improper Certificate Validation
Affects strimzi-kafka-operatorSource CVE Database V5
Not known to be exploited · CVSS 5.9 Medium : upgrade to 0.51.1 when convenient.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 9% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.51.1
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 20 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade strimzi-kafka-operator to 0.51.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| strimzistrimzi-kafka-operator | Affected
| Fixed in
|
AI-suggested
The primary mitigation is to upgrade the strimzi-kafka-operator to version 0.50.1 or later, where the certificate validation logic is corrected. Until upgrade is possible, organizations should avoid using multiple CA certificates in the trusted CA chain configuration for Kafka Connect and MirrorMaker 2 operands, limiting to a single trusted CA certificate to reduce risk. Review and audit the CA chain configurations to ensure only intended root CAs are trusted. Implement strict access controls to limit who can modify Strimzi configurations and CA chains, reducing the risk of privilege abuse. Monitor Kafka broker connections and TLS certificate usage for anomalies that could indicate misuse of intermediate CA certificates. Employ network segmentation and zero-trust principles around Kafka clusters to limit exposure. Finally, maintain up-to-date backups and incident response plans in case of compromise.
Description
Strimzi provides a way to run an Apache Kafka cluster on Kubernetes or OpenShift in various deployment configurations. From 0.47.0 to before 0.50.1, when a chain consisting of multiple CA (Certificate Authority) certificates is used in the trusted certificates configuration of a Kafka Connect operand or of the target cluster in the Kafka MirrorMaker 2 operand, all of the certificates that are part of the CA chain will be trusted individually when connecting to the Apache Kafka cluster. Due to this error, the affected operand (Kafka Connect or Kafka MirrorMaker 2) might accept connections to Kafka brokers using server certificates signed by one of the other CAs in the CA chain and not just by the last CA in the chain. This issue is fixed in Strimzi 0.50.1.