CVE-2020-17519: Apache Flink Improper Access Control Vulnerability

High severity, CVSS 7.5. Actively exploited: in CISA KEV since 2024-05-23. EPSS: 97.8% chance of exploitation in the next 30 days.

A change introduced in Apache Flink 1.11.0 (and released in 1.11.1 and 1.11.2 as well) allows attackers to read any file on the local filesystem of the JobManager through the REST interface of the JobManager process. Access is restricted to files accessible by the JobManager process. All users should upgrade to Flink 1.11.3 or 1.12.0 if their Flink instance(s) are exposed. The issue was fixed in commit b561010b0ee741543c3953306037f00d7a9f0801 from apache/flink:master.

Affected products

• Apache Flink: from 1.11.0, before 1.11.3 (fixed in 1.11.3)

Published 2021-01-05. Last modified 2026-06-17.