Apache Flink directory traversal attack: reading remote files through the REST API
CVE-2020-17519

7.5HIGH

Key Information:

Vendor: Apache
Status: Apache Flink
Vendor: CVE Published:; 5 January 2021

Badges

👾 Exploit Exists🟡 Public PoC🟣 EPSS 97%🦅 CISA Reported

Summary

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.

CISA Reported

CISA provides regional cyber and physical services to support security and resilience across the United States. CISA monitor the most dangerious vulnerabilities and have identifed as being exploited but is not known by the CISA to be used in ransomware campaigns. This is subject to change at pace

The CISA's recommendation is: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Affected Version(s)

Apache Flink Apache Flink 1.11.0 to 1.11.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2020-17519
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