Apache Airflow: Execution API HITL Endpoints Missing Per-Task Authorization

Vulnerability

Overview

CVE-2026-30911 is a missing authorization vulnerability in the Execution API's Human-in-the-Loop (HITL endpoints of Apache Airflow versions 3.1.0 through 3.1.7. The root cause is that the HITL endpoints do not validate whether the requesting task instance is authorized to access, approve, or reject workflows belonging to another task instance. This allows any authenticated task instance to perform actions on HITL workflows of any other task instance [1][2][3].

Exploitation

An attacker who has authenticated access to the Airflow environment can exploit this by sending crafted requests to the HITL endpoints. No special privileges beyond being an authenticated task instance are required. The attack surface is the Execution API's HITL endpoints, which are exposed to authenticated but lack per-task authorization checks [2][3].

Impact

A successful exploit allows an attacker to read, approve, or reject HITL workflows belonging to any other task instance. This could lead to unauthorized approval of malicious workflows or disruption of legitimate workflows, or exposure of sensitive workflow information [2][3].

Mitigation

The issue is fixed in Apache Airflow 3.1.8. Users are strongly recommended to upgrade to this version or later. The fix adds task instance validation to ensure that approval actions come from the correct task, as implemented in pull request #62886 [3][4]. No workarounds have been published.