CVE-2025-50864
Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
20/08/2025
Last modified:
26/01/2026
Description
An Origin Validation Error in the elysia-cors library thru 1.3.0 allows attackers to bypass Cross-Origin Resource Sharing (CORS) restrictions. The library incorrectly validates the supplied origin by checking if it is a substring of any domain in the site's CORS policy, rather than performing an exact match. For example, a malicious origin like "notexample.com", "example.common.net" is whitelisted when the site's CORS policy specifies "example.com." This vulnerability enables unauthorized access to user data on sites using the elysia-cors library for CORS validation.
Impact
Base Score 3.x
6.50
Severity 3.x
MEDIUM
References to Advisories, Solutions, and Tools
- http://elysiajs.com
- https://github.com/elysiajs/elysia-cors/blob/main/src/index.ts
- https://github.com/elysiajs/elysia-cors/commit/9b9eb92e32a7a4b43b6d5108668941701c33e221
- https://github.com/elysiajs/elysia-cors/tree/main
- https://medium.com/@raghavagrawal_23036/cors-bypass-in-popular-opensource-library-ad27fb41e16a