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CVE-2025-66457 Detail

Description

Elysia is a Typescript framework for request validation, type inference, OpenAPI documentation and client-server communication. Versions 1.4.17 and below are subject to arbitrary code execution from cookie config. When dynamic cookies are enabled (e.g. there an existing cookie schema), the cookie config is injected into the compiled route without first being sanitised. Availability of this exploit is generally low, but when combined with GHSA-hxj9-33pp-j2cc, it allows for a full RCE chain. An attack requires write access to either the Elysia app's source code (in which case the vulnerability is meaningless) or write access to the cookie config (perhaps where it is assumed to be provisioned by the environment). This issue is fixed in version 1.4.18.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 7.5 HIGH
Vector:  CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/elysiajs/elysia/commit/26935bf76ebc43b4a43d48b173fc853de43bb51e GitHub, Inc.
https://github.com/elysiajs/elysia/commit/3af978663e437dccc6c1a2a3aff4b74e1574849e GitHub, Inc.
https://github.com/elysiajs/elysia/pull/1564 GitHub, Inc.
https://github.com/elysiajs/elysia/security/advisories/GHSA-8vch-m3f4-q8jf GitHub, Inc.
https://github.com/elysiajs/elysia/security/advisories/GHSA-hxj9-33pp-j2cc GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-94 Improper Control of Generation of Code ('Code Injection') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-66457
NVD Published Date:
12/09/2025
NVD Last Modified:
12/09/2025
Source:
GitHub, Inc.