CVE-2021-41101
CORS `Access-Control-Allow-Origin` settings are too lenient
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).
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
5.7
CORS `Access-Control-Allow-Origin` settings are too lenient
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).
- Record
CVE-2021-41101- CVSS 3.1
- 5.7 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2021-28240
5.7
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).
- Record
EUVD-2021-28240- CVSS 3.1
- 5.7 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N - Updated
- 2026-11-03
NVD
5.7
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).
- Record
CVE-2021-41101- CVSS 3.1
- 5.7 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N - CVSS 2.0
- 3.5 Low
AV:N/AC:M/Au:S/C:P/I:N/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
5.7
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).
- Record
CVE-2021-41101- CVSS 3.1
- 5.7 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-41101 is a medium vulnerability (CVSS 5.7) in Wire Server, published September 30, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.71%, the 53rd percentile. No source names a fixed version.