@koa/cors npm provides Cross-Origin Resource Sharing (CORS) for koa, a web framework for Node.js. Prior to version 5.0.0, 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. Version 5.0.0 fixes this vulnerability.
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cve-icon MITRE Information

Status: PUBLISHED

Assigner: GitHub_M

Published: 2023-12-11T22:42:17.547Z

Updated: 2023-12-11T22:42:17.547Z

Reserved: 2023-11-30T13:39:50.865Z


Link: CVE-2023-49803

JSON object: View

cve-icon NVD Information

Status : Analyzed

Published: 2023-12-11T23:15:07.620

Modified: 2023-12-14T20:03:24.677


Link: CVE-2023-49803

JSON object: View

cve-icon Redhat Information

No data.

CWE