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Fencer Vulns
high 8.8

CVE-2023-25194 in the critical feed json

Apache Kafka Connect API: Possible RCE/Denial of service attack via SASL JAAS JndiLoginModule configuration using Kafka Connect

published 2023-02-07 3 y ago modified 2026-06-17 4 mo ago also GHSA-26f8-x7cc-wqpc , EUVD-2023-0598

cvss
8.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
95.8%
EPSS 95.8% chance of exploitation in 30 days, percentile 99.8%
public exploits
1
Metasploit, plus a Nuclei check

Summary

A possible security vulnerability has been identified in Apache Kafka Connect API. This requires access to a Kafka Connect worker, and the ability to create/modify connectors on it with an arbitrary Kafka client SASL JAAS config and a SASL-based security protocol, which has been possible on Kafka Connect clusters since Apache Kafka Connect 2.3.0. When configuring the connector via the Kafka Connect REST API, an authenticated operator can set the `sasl.jaas.config` property for any of the connector's Kafka clients to "com.sun.security.auth.module.JndiLoginModule", which can be done via the `producer.override.sasl.jaas.config`, `consumer.override.sasl.jaas.config`, or `admin.override.sasl.jaas.config` properties. This will allow the server to connect to the attacker's LDAP server and deserialize the LDAP response, which the attacker can use to execute java deserialization gadget chains on the Kafka connect server. Attacker can cause unrestricted deserialization of untrusted data (or) RCE vulnerability when there are gadgets in the classpath.

Since Apache Kafka 3.0.0, users are allowed to specify these properties in connector configurations for Kafka Connect clusters running with out-of-the-box configurations. Before Apache Kafka 3.0.0, users may not specify these properties unless the Kafka Connect cluster has been reconfigured with a connector client override policy that permits them.

Since Apache Kafka 3.4.0, we have added a system property ("-Dorg.apache.kafka.disallowed.login.modules") to disable the problematic login modules usage in SASL JAAS configuration. Also by default "com.sun.security.auth.module.JndiLoginModule" is disabled in Apache Kafka Connect 3.4.0.

We advise the Kafka Connect users to validate connector configurations and only allow trusted JNDI configurations. Also examine connector dependencies for vulnerable versions and either upgrade their connectors, upgrading that specific dependency, or removing the connectors as options for remediation. Finally, in addition to leveraging the "org.apache.kafka.disallowed.login.modules" system property, Kafka Connect users can also implement their own connector client config override policy, which can be used to control which Kafka client properties can be overridden directly in a connector config and which cannot.

Patch / fix

  • maven org.apache.kafka:connect 3.4.0
  • Apache Software Foundation Apache Kafka Connect API 3.4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-25194 updated cvss 8.8

kafka: RCE/DoS via SASL JAAS JndiLoginModule configuration in Kafka Connect

  • Red Hat streams for Apache Kafka kafka-connect kafka-connect
    affected: no fix available
  • Red Hat AMQ Streams 2.2.1
    fixed: vendor fix RHSA-2023:1241
  • Red Hat AMQ Streams 2.4.0
    fixed: vendor fix RHSA-2023:3223
  • Red Hat build of Apicurio Registry 2 kafka-connect kafka-connect
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Timeline

  1. First public exploit (Metasploit exploit/multi/http/apache_druid_cve_2023_25194)
  2. Published

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
total
Assessed
19 mo ago

Exploit prediction

95.81% chance of exploitation in the next 30 days, higher than 99.8% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

CVSS scores

assigned by version score vector
CISA ADP 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
GitHub 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
maven org.apache.kafka:connect
>=2.3.0, <3.4.0
3.4.0

Affected products

  • Apache Software Foundation Apache Kafka Connect API

Classification

Weakness
  • CWE-502 Deserialization of Untrusted Data

References

Sources

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