pyLoad is vulnerable to attacks that bypass localhost restrictions, enabling the creation of arbitrary packages

链接： https://github.com/advisories/GHSA-x698-5hjm-w2m5

仓库 Star： 3530

CVSS 评分： 7.5

参考链接：

描述：

Summary

Any unauthenticated attacker can bypass the localhost restrictions posed by the application and utilize this to create arbitrary packages.

Details

Any unauthenticated attacker can bypass the localhost restrictions posed by the application and utilize this to create arbitrary packages. This is done by changing the Host header to the value of 127.0.0.1:9666.

PoC

The application has middleware that prevents access to several routes by checking whether the Host header has a specific value. We bypassed this restriction.

https://github.com/pyload/pyload/blob/4159a1191ec4fe6d927e57a9c4bb8f54e16c381d/src/pyload/webui/app/blueprints/cnl_blueprint.py#L21-L36

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
#: decorator
def local_check(func):
    @wraps(func)
    def wrapper(*args, **kwargs):
        remote_addr = flask.request.environ.get("REMOTE_ADDR", "0")
        http_host = flask.request.environ.get("HTTP_HOST", "0")

        if remote_addr in ("127.0.0.1", "::ffff:127.0.0.1", "::1", "localhost") or http_host in (
            "127.0.0.1:9666",
            "[::1]:9666",
        ):
            return func(*args, **kwargs)
        else:
            return "Forbidden", 403

    return wrapper

Below we see that the ‘/flash/add’ endpoint uses the middleware above.

https://github.com/pyload/pyload/blob/4159a1191ec4fe6d927e57a9c4bb8f54e16c381d/src/pyload/webui/app/blueprints/cnl_blueprint.py#L56-L58C11

1
2
3
@bp.route("/flash/add", methods=["POST"], endpoint="add")
@local_check
def add():

Notice how we are not authorized to access this endpoint when sending a request.
image

However, if we set the Host header to be 127.0.0.1:9666, we notice the request returns success.
image

Checking the front end as an admin, we now see that this did indeed succeed.
image

Impact

An unauthenticated user can perform actions that should only be available to authenticated users.

安全公告
#Github Advisory
pyLoad is vulnerable to attacks that bypass localhost restrictions, enabling the creation of arbitrary packages
http://example.com/2025/07/08/github_2289382568/
作者
lianccc
发布于
2025年7月8日
许可协议