The vulnerability CVE-2026-3418 in WSO2 API Manager allows authenticated users with publisher privileges to upload files without sufficient validation of file type or destination. This lack of validation enables files to be written to arbitrary locations accessible by the server. Depending on deployment specifics and how uploaded files are processed, this could lead to execution of malicious content, resulting in remote code execution. The vulnerability affects versions 4.4.0, 4.5.0, and 4.6.0. The CVSS 3.1 score is 9.1 (critical), indicating high impact on confidentiality, integrity, and availability. No official patch or remediation guidance is currently provided by the vendor.

An authenticated publisher can upload arbitrary files to server-accessible locations, which may lead to remote code execution if the uploaded files are executed by the server. This compromises confidentiality, integrity, and availability of the affected system. The vulnerability requires high privileges (publisher role) and network access but no user interaction. There are no known exploits in the wild at this time.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict publisher privileges to trusted users only and monitor for suspicious file uploads. Review deployment configurations to limit execution permissions on uploaded files and consider additional validation or filtering at the application or network level.