Apache Airflow FAB Provider Azure AD OAuth JWT Signature Verification Authentication Bypass

This repository is a small standalone exploit PoC consisting of a README and a single Python script, exploit.py. It targets CVE-2026-59243 in Apache Airflow's FAB auth manager provider for Azure OAuth, where id_token signature verification is disabled by default in vulnerable apache-airflow-providers-fab versions. The exploit abuses this to complete the OAuth flow and obtain an authenticated Airflow Admin session without valid credentials, then uses the resulting API token to trigger a DAG run that executes attacker-controlled commands. Repository structure is minimal: README.md documents the vulnerability, affected/fixed versions, prerequisites, and usage; exploit.py implements the full attack chain using only Python standard library modules (argparse, urllib, cookiejar, json, time). The script hardcodes DAG_ID = 'pwn', generates a unique logical_date for each run, maintains cookies across redirects, and includes a custom redirect handler that rewrites OAuth redirects from 127.0.0.1 or localhost to the target host so the attacker can complete the flow remotely. Main exploit capabilities: (1) initiate OAuth login at /auth/login/azure; (2) follow redirect chain and preserve cookies; (3) recover the _token JWT cookie after login; (4) POST to /api/v2/dags/pwn/dagRuns with JSON containing conf.cmd; and (5) execute either an arbitrary shell command or a generated bash reverse shell. The exploit is operational rather than a mere detector because it performs authentication bypass and attempts real code execution. It is not framework-based and appears to be a purpose-built PoC for this Airflow vulnerability.

Repository is a standalone proof-of-concept for CVE-2026-59243, a JWT signature verification bypass in Apache Airflow's FAB Auth Manager Azure AD OAuth path. The core issue described is that affected Airflow code defaults verify_signature to False and decodes id_token values with signature verification disabled, enabling pre-auth identity forgery if an attacker can inject a JWT into the OAuth callback flow. The repo contains documentation in English and Korean, a one-line patch diff showing the upstream fix (False -> True), a Bash advisory-monitoring script unrelated to exploitation, and a self-contained Dockerized PoC under poc/. The PoC consists of a Flask server (poc/server.py) that intentionally reproduces the vulnerable behavior by accepting any JWT via /oauth/callback and /admin using jwt.decode(..., options={"verify_signature": False}), an exploit script (poc/exploit_airflow_jwt.py) that forges an alg:none JWT with Admin role claims and uses it to authenticate and access the admin endpoint, plus Dockerfile/docker-compose/run.sh to build and run the demo locally on 127.0.0.1:5002. Main exploit capability: forge arbitrary identities and roles, including Admin, without possessing signing keys. This is an actual exploit PoC rather than a detector, and while the payload is basic and hardcoded, it is functional and operational.