Bola Idor in Rocket with Basic Auth

Broken Object Level Authorization (BOLA) occurs when an API lacks proper authorization checks such that one object can be accessed or manipulated simply by changing its identifier. In the Rocket web framework, this commonly arises when route parameters like :id are used to locate a record without verifying that the authenticated actor is entitled to access that specific object. When Basic Auth is used for authentication, the presence of a valid username/password pair does not imply authorization for any given resource. If Rocket routes rely only on authentication (e.g., verifying credentials) and skip per-request ownership or scope checks, an authenticated user can iterate through IDs and read or modify data that belongs to other users.

Consider a Rocket endpoint that retrieves a user’s profile by ID:

#[get("/profile/<id>")]
fn get_profile(id: u32, user: Auth<User>) -> Result<Json<Profile>, Status> {
    // BOLA risk: no check that profile.id == user.id
    Profile::find_by_id(id).map(Json).unwrap_or(Err(Status::NotFound))
}

Here, user is populated by Basic Auth middleware, confirming identity but not authorization for the requested id. An attacker who knows or guesses another user’s numeric ID can retrieve or modify it because Rocket does not enforce that the authenticated user owns the object. Identical issues appear in endpoints that accept path parameters like /users/:user_id/settings or /projects/:project_id without verifying that the authenticated subject matches the supplied identifier.

BOLA is frequently coupled with IDOR when predictable, sequential IDs are used. Basic Auth does not mitigate this; it only provides a static credential per request. In Rocket, if authorization logic is omitted or duplicated across handlers, the API’s unauthenticated attack surface allows an attacker to iterate IDs and observe differences in responses (200 vs 403/404), confirming the presence of BOLA. This becomes especially risky when combined with other checks such as lack of rate limiting, where attackers can automate enumeration at scale.

Real-world analogies include scenarios where an authenticated user can access /api/v1/invoices/12345 simply by supplying valid Basic Auth headers, even when the invoice belongs to another tenant. OWASP API Top 10 A1: Broken Object Level Authorization explicitly covers this class of risk. PCI-DSS and SOC2 also require that subjects be restricted to the minimum set of objects necessary; BOLA violates that principle by allowing broad access based on weak or missing authorization checks.

To detect such issues, middleBrick scans unauthenticated and authenticated states, comparing responses across IDs and evaluating whether authorization checks are consistently applied. It maps findings to OWASP API Top 10 and frameworks like PCI-DSS and SOC2, highlighting endpoints where authentication does not equate to authorization. By correlating spec definitions with runtime behavior, middleBrick surfaces BOLA patterns that may otherwise remain hidden in route-level code.

Remediation centers on ensuring that every access to an object includes an explicit authorization check tying the authenticated subject to the object’s ownership or allowed scope. With Basic Auth in Rocket, you should not rely on authentication alone; you must enforce per-request checks in handlers or via fairings/guards. Below are concrete patterns to adopt.

1. Verify ownership within the handler

Compare the authenticated user’s ID with the object’s owner ID before proceeding:

#[get("/profile/<id>")]
fn get_profile(id: u32, user: Auth<User>) -> Result<Json<Profile>, Status> {
    let profile = Profile::find_by_id(id).ok_or(Status::NotFound)?;
    if profile.user_id != user.id {
        return Err(Status::Forbidden);
    }
    Ok(Json(profile))
}

This ensures that even with valid Basic Auth, users can only access profiles they own. The check is explicit and fails closed with a 403 if ownership does not match.

2. Use request guards to enforce scoping

Create a custom request guard that validates ownership before reaching the handler. This centralizes authorization logic and reduces duplication:

struct AuthedProfile {
    profile: Profile,
}

#[rocket::async_trait]
impl<'r> FromRequest<'r> for AuthedProfile {
    type Error = ();

    async fn from_request(request: &Request<'>) -> request::Outcome<Self, Self::Error> {
        let id = request.rocket().fairing::().ok_or(())?; // example: extract id from route
        let user = request.guard::<&User>().await.succeeded().ok_or(())?;
        let profile = Profile::find_by_id(id).ok_or(())?;
        if profile.user_id != user.id {
            return Outcome::Failure((Status::Forbidden, ()));
        }
        Outcome::Success(AuthedProfile { profile })
    }
}

#[get("/profile/<id>")]
fn get_profile(profile: AuthedProfile) -> Result<Json<Profile>, Status> {
    Ok(Json(profile.profile))
}

This approach encapsulates authorization and leverages Rocket’s request guard system to fail early when access is not permitted.

3. Parameterize queries with user context

Ensure database queries include the user context so that invalid IDs simply return 404 rather than exposing existence:

#[get("/projects/<project_id>")]
fn get_project(project_id: u32, user: Auth<User>) -> Result<Json<Project>, Status> {
    let project = Project::find_by_id_and_owner(project_id, user.id)
        .ok_or(Status::NotFound)?;
    Ok(Json(project))
}

On the backend, find_by_id_and_owner should include a WHERE clause that matches both ID and owner, preventing horizontal privilege escalation.

4. Avoid exposing predictable IDs when not necessary

Consider using UUIDs or opaque identifiers instead of sequential integers to reduce the risk of ID enumeration. If integers are required, enforce strict authorization on every lookup and add rate limiting to deter brute-force attempts.

5. Combine with other protections

Basic Auth should be transmitted over TLS to prevent credential interception. Additionally, apply rate limiting and monitoring to detect enumeration attempts. middleBrick’s scans can verify that such controls are present and that endpoints consistently reject unauthorized access across different IDs.

By embedding ownership checks in handlers, guards, or query builders, Rocket APIs can effectively neutralize BOLA risks introduced by predictable identifiers, even when Basic Auth is used for authentication.