CVE-2025-66457

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/elysiajs/elysia/commit/26935bf76ebc43b4a43d48b173fc853de43bb51e	Patch
https://github.com/elysiajs/elysia/commit/3af978663e437dccc6c1a2a3aff4b74e1574849e	Patch
https://github.com/elysiajs/elysia/pull/1564	Issue Tracking Patch
https://github.com/elysiajs/elysia/security/advisories/GHSA-8vch-m3f4-q8jf	Exploit Patch Vendor Advisory
https://github.com/elysiajs/elysia/security/advisories/GHSA-hxj9-33pp-j2cc	Not Applicable
https://github.com/sportshead/elysia-poc	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:elysiajs:elysia:*:*:*:*:*:node.js:*:*

History

No history.

Information

Published : 2025-12-09 20:15

Updated : 2025-12-17 14:27

NVD link : CVE-2025-66457

Mitre link : CVE-2025-66457

CVE.ORG link : CVE-2025-66457

JSON object : View

Products Affected

elysiajs

elysia

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

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