CVE-2023-49803

HIGH EPSS 19.6%
Published Dec 11, 20232y ago · Modified Jun 17, 20262w ago
7.5 CVSS 3.1
High
Find Similar
Published Dec 11, 2023 2y ago
Last Modified Jun 17, 2026 2w ago

Description

@koa/cors npm provides Cross-Origin Resource Sharing (CORS) for koa, a web framework for Node.js. Prior to version 5.0.0, the middleware operates in a way that if an allowed origin is not provided, it will return an `Access-Control-Allow-Origin` header with the value of the origin from the request. This behavior completely disables one of the most crucial elements of browsers - the Same Origin Policy (SOP), this could cause a very serious security threat to the users of this middleware. If such behavior is expected, for instance, when middleware is used exclusively for prototypes and not for production applications, it should be heavily emphasized in the documentation along with an indication of the risks associated with such behavior, as many users may not be aware of it. Version 5.0.0 fixes this vulnerability.

CVSS Details

Base Score
7.5
Exploitability
3.9
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity High
Availability None

Threat Intelligence

EPSS Exploit Probability
19.6% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-346

Affected Products 1

VendorProductVersionRange
koajscross-origin_resource_sharing_for_koa* <5.0.0

References 2

  • github.com https://github.com/koajs/cors/commit/f31dac99f5355c41e7d4dd3c4a80c5f154941a11
    Patch
  • github.com https://github.com/koajs/cors/security/advisories/GHSA-qxrj-hx23-xp82
    Vendor Advisory

Remediation

  • github.com https://github.com/koajs/cors/commit/f31dac99f5355c41e7d4dd3c4a80c5f154941a11
    Patch