Apache Flink processes user supplied SQL queries. The vulnerability occurs when Flink's SQL code generator interpolates user‑controlled strings into Java code without proper escaping. This allows an authenticated user with query submission rights to break out of string literals, inject arbitrary Java expressions, and execute code on the TaskManager nodes. The impact is the ability to run any code on the cluster, leading to full system compromise.

Apache Software Foundation product Apache Flink versions 1.15.0 through 1.20.x and 2.0.0 through 2.x are affected. Users of Flink 1.15.0+ that enable JSON functions and of 1.17.0+ that use LIKE expressions with ESCAPE clauses are included.

The flaw offers remote code execution capability only to users who can submit queries, so it requires authenticated privileges. Nevertheless, many Flink deployments grant such privileges to application developers or service accounts, making the failure surface large. The CVSS score of 8.1 indicates high severity. EPSS data is unavailable and the vulnerability is not listed in CISA KEV, but the lack of a publicly released exploit does not diminish the importance of patching. Attackers would craft a specially formed SQL statement to trigger the code generation path that injects malicious Java code.