GHSA-r5vv-ff45-prp2 datamodel-code-generator: Authorization / request headers leaked to cross-origin redirect target when fetching remote schemas

• PyPI datamodel-code-generator: < 0.63.0 → fixed in 0.63.0

Summary When `datamodel-code-generator` fetches a remote schema and follows an HTTP redirect, it re-sends the original request headers, including any `Authorization` header, to the redirect target even when the redirect changes origin (host/port/scheme). Credentials that an operator scoped to a trusted schema host are therefore forwarded to an attacker-controlled or otherwise different host, leaking them. Details In `src/datamodel_code_generator/http.py`, `get_body()` follows redirects manually and re-issues each hop with the same `headers` argument, with no check that the origin is unchanged: ```python for redirect_count in range(MAX_HTTP_REDIRECTS + 1): _validate_url_for_fetch(current_url, allow_private_network=allow_private_network) response = httpx.get(current_url, headers=headers, follow_redirects=False, ...) # same headers every hop if (redirect_url := _get_redirect_url(httpx, current_url, response)) is None: break current_url = redirect_url ``` Browsers and HTTP clients such as `requests`/`httpx` strip `Authorization` when a redirect crosses origin; here it is preserved unconditionally. Headers are operator-supplied via `--http-headers` (and credentials can also arrive through `--url` userinfo), so a redirect from the trusted host to any other host discloses them. PoC Self-contained reproducer: https://gist.github.com/thegr1ffyn/ade3035d7f2be95e16f11698259cdbc2 Host A (the trusted schema host) 302-redirects to host B (a different origin) which records received headers; the request carries an auth token scoped to A. (The PoC uses loopback servers; `allow_private_network=True` is only to avoid the separate SSRF guard blocking loopback and has no bearing on the leak.) Impact Exposure of sensitive information to an unauthorized actor (CWE-200). Affects operators who pass authentication headers/credentials to fetch a remote schema (`--http-headers`, `--url` with userinfo) when the configured host issues a redirect to a different origin — e.g. a compromised or open-redirect-prone schema host, or a redirect chain influenced by an attacker-supplied `$ref`. The leaked credential can then be replayed against the trusted host. This is a credential-scoping weakness secondary to, and in the same component as, the project's other SSRF hardening. Suggested remediation When a redirect changes the origin (scheme/host/port), drop `Authorization` and other sensitive headers before following it, matching the behavior of mainstream HTTP clients. Maintainer status Confirmed by maintainer review and regression tests. The private fix PR was merged and released in `0.63.0`: https://github.com/koxudaxi/datamodel-code-generator-ghsa-r5vv-ff45-prp2/pull/1 Fix summary: strip `Authorization`, `Cookie`, and `Proxy-Authorization` headers when a redirect crosses origin; preserve headers for same-origin redirects. Release status: fixed in `0.63.0`; `0.62.0` and earlier are affected. Validation: `uv run --group test --extra http pytest tests/test_http.py` passed locally for the redirect regression coverage; `uv run --group fix ruff check src/datamodel_code_generator/http.py tests/test_http.py` passed. Submitted by: Hamza Haroon (thegr1ffyn)