CVE-2026-41690
HIGH EPSS 22.7%
Published May 8, 20261mo ago · Modified Jun 17, 20262w ago
8.6 CVSS 3.1
Published May 8, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago
Description
18next-http-middleware is a middleware to be used with Node.js web frameworks like express or Fastify and also for Deno. Versions prior to 3.9.3 allow an unauthenticated HTTP client to pollute Object.prototype in the Node.js process hosting the middleware, via two unvalidated entry points that reach internal object-key writes: getResourcesHandler and missingKeyHandler. This can break authorisation checks (if (user.isAdmin) returning true for any user), cause type-confusion DoS, and depending on downstream code it can be chained into RCE.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Low
Integrity High
Availability Low
Threat Intelligence
EPSS Exploit Probability
22.7% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 2
CWE-1321
CWE-22 Path Traversal Resource Mgmt
References 1
- github.com https://github.com/i18next/i18next-http-middleware/security/advisories/GHSA-5fgg-jcpf-8jjw
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.