Description
Deserialization of Untrusted Data vulnerability in Apache Storm. Versions Affected: before 2.8.6. Description: When processing topology credentials submitted via the Nimbus Thrift API, Storm deserializes the base64-encoded TGT blob using ObjectInputStream.readObject() without any class filtering or validation. An authenticated user with topology submission rights could supply a crafted serialized object in the "TGT" credential field, leading to remote code execution in both the Nimbus and Worker JVMs. Mitigation: 2.x users should upgrade to 2.8.6. Users who cannot upgrade immediately should monkey-patch an ObjectInputFilter allow-list to ClientAuthUtils.deserializeKerberosTicket() restricting deserialized classes to javax.security.auth.kerberos.KerberosTicket and its known dependencies. A guide on how to do this is available in the release notes of 2.8.6. Credit: This issue was discovered by K.
Problem types
CWE-502 Deserialization of Untrusted Data
Product status
Any version before 2.8.6
Credits
K
References
www.openwall.com/lists/oss-security/2026/04/12/6
storm.apache.org/2026/04/12/storm286-released.html