CVE-2024-27933

NVD	https://nvd.nist.gov/vuln/detail/CVE-2024-27933
CWE	https://cwe.mitre.org/data/definitions/863.html

Deno is a JavaScript, TypeScript, and WebAssembly runtime. In version 1.39.0, use of raw file descriptors in op_node_ipc_pipe() leads to premature close of arbitrary file descriptors, allowing standard input to be re-opened as a different resource resulting in permission prompt bypass. Node child_process IPC relies on the JS side to pass the raw IPC file descriptor to op_node_ipc_pipe(), which returns a IpcJsonStreamResource ID associated with the file descriptor. On closing the resource, the raw file descriptor is closed together.

Use of raw file descriptors in op_node_ipc_pipe() leads to premature close of arbitrary file descriptors. This allow standard input (fd 0) to be closed and re-opened for a different resource, which allows a silent permission prompt bypass. This is exploitable by an attacker controlling the code executed inside a Deno runtime to obtain arbitrary code execution on the host machine regardless of permissions.

This bug is known to be exploitable. There is a working exploit that achieves arbitrary code execution by bypassing prompts from zero permissions, additionally abusing the fact that Cache API lacks filesystem permission checks. The attack can be conducted silently as stderr can also be closed, suppressing all prompt outputs.

Version 1.39.1 fixes the bug.

Weakness

The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.

Extended Description

Assuming a user with a given identity, authorization is the process of determining whether that user can access a given resource, based on the user’s privileges and any permissions or other access-control specifications that apply to the resource. When access control checks are incorrectly applied, users are able to access data or perform actions that they should not be allowed to perform. This can lead to a wide range of problems, including information exposures, denial of service, and arbitrary code execution.

Potential Mitigations

Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) [REF-229] to enforce the roles at the appropriate boundaries.
Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page.
One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.

Incorrect Authorization

Weakness

Extended Description

Potential Mitigations

References