CVE-2023-49803 – @koa/cors

Package

Manager: npm
Name: @koa/cors
Vulnerable Version: >=0 <5.0.0

Severity

Level: High

CVSS v3.1: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N

EPSS: 0.00131 pctl0.3348

Details

Overly permissive origin policy Currently, the middleware operates in a way that if an allowed origin is not provided, it will return an `Access-Control-Allow-Origin` header with the value of the origin from the request. This behavior completely disables one of the most crucial elements of browsers - the Same Origin Policy (SOP), this could cause a very serious security threat to the users of this middleware. If such behavior is expected, for instance, when middleware is used exclusively for prototypes and not for production applications, it should be heavily emphasized in the documentation along with an indication of the risks associated with such behavior, as many users may not be aware of it.

Metadata

Created: 2023-12-11T21:46:21Z
Modified: 2023-12-12T00:46:36Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/12/GHSA-qxrj-hx23-xp82/GHSA-qxrj-hx23-xp82.json
CWE IDs: ["CWE-346"]
Alternative ID: GHSA-qxrj-hx23-xp82
Finding: F086
Auto approve: 1