title: CORS `Access-Control-Allow-Origin` settings are too lenient
description: wire-server is an open-source back end for Wire, a secure collaboration platform. Before version 2.106.0, the CORS ` Access-Control-Allow-Origin ` header set by `nginz` is set for all subdomains of `.wire.com` (including `wire.com`). This means that if somebody were to find an XSS vector in any of the subdomains, they could use it to talk to the Wire API using the user's Cookie. A patch does not exist, but a workaround does. To make sure that a compromise of one subdomain does not yield access to the cookie of another, one may limit the `Access-Control-Allow-Origin` header to apps that actually require the cookie (account-pages, team-settings and the webapp).
problem types: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
affected:
{
product: wire-server
vendor: wireapp
versions:
status: affected, version: < 2.106.0
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 5.7
baseSeverity: MEDIUM
confidentialityImpact: HIGH
integrityImpact: NONE
privilegesRequired: LOW
scope: UNCHANGED
userInteraction: REQUIRED
vectorString: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N
version: 3.1
]