CVE-2018-17194: Apache Nifi

High severity, CVSS 7.5. EPSS: 3% chance of exploitation in the next 30 days.

When a client request to a cluster node was replicated to other nodes in the cluster for verification, the Content-Length was forwarded. On a DELETE request, the body was ignored, but if the initial request had a Content-Length value other than 0, the receiving nodes would wait for the body and eventually timeout. Mitigation: The fix to check DELETE requests and overwrite non-zero Content-Length header values was applied on the Apache NiFi 1.8.0 release. Users running a prior 1.x release should upgrade to the appropriate release.

Affected products

• Apache Nifi: from 1.0.0, up to and including 1.7.1

Published 2018-12-19. Last modified 2026-06-17.