Description

Elysia is a Typescript framework for request validation, type inference, OpenAPI documentation and client-server communication. Versions 1.4.0 through 1.4.16 contain a prototype pollution vulnerability in `mergeDeep` after merging results of two standard schema validations with the same key. Due to the ordering of merging, there must be an any type that is set as a standalone guard, to allow for the `__proto__ prop` to be merged. When combined with GHSA-8vch-m3f4-q8jf this allows for a full RCE by an attacker. This issue is fixed in version 1.4.17. To workaround, remove the `__proto__ key` from body.

INFO

Published Date :

2025-12-09T19:43:10.252Z

Last Modified :

2025-12-09T20:35:44.683Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2025-66456 vulnerability.

Vendors Products
Elysiajs
  • Elysia
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2025-66456.

URL Resource
https://github.com/elysiajs/elysia/commit/26935bf76ebc43b4a43d48b173fc853de43bb51e cve-icon cve-icon
https://github.com/elysiajs/elysia/commit/3af978663e437dccc6c1a2a3aff4b74e1574849e cve-icon cve-icon
https://github.com/elysiajs/elysia/pull/1564 cve-icon cve-icon
https://github.com/elysiajs/elysia/security/advisories/GHSA-8vch-m3f4-q8jf cve-icon cve-icon cve-icon
https://github.com/elysiajs/elysia/security/advisories/GHSA-hxj9-33pp-j2cc cve-icon cve-icon cve-icon
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