Deserialization in Apache Kafka
CVE-2025-27819
In CVE-2023-25194, we announced the RCE/Denial of service attack via SASL JAAS JndiLoginModule configuration in Kafka Connect API. But not only Kafka Connect API is vulnerable to this attack, the Apache Kafka brokers also have this vulnerability. To exploit this vulnerability, the attacker needs to be able to connect to the Kafka cluster and have the AlterConfigs permission on the cluster resource. 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 3.4.0, and "com.sun.security.auth.module.JndiLoginModule,com.sun.security.auth.module.LdapLoginModule" is disabled by default in in Apache Kafka 3.9.1/4.0.0
Vulnerability class: Insecure Deserialization
EPSS: 0.009 (55.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Apache Kafka
- Apache Software Foundation Kafka — versions 2.0.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@apache.org (vendor-advisory, Vendor Advisory)
Frequently asked questions
- What is CVE-2025-27819?
- CVE-2025-27819 is a high-severity vulnerability in Apache Kafka, classified under Deserialization of Untrusted Data. CVSS score: 7.5/10. Published 2025-06-10.
- How severe is CVE-2025-27819?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2025-27819 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.