Bulk list client endpoint exposes too much metadata about a client
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-200.
Summary
wire-server is an open-source back end for Wire, a secure collaboration platform. In wire-server from version 2021-02-16 and before version 2021-03-02, the client metadata of all users was exposed in the `GET /users/list-clients` endpoint. The endpoint could be used by any logged in user who could request client details of any other user (no connection required) as far as they can find their User ID. The exposed metadata included id, class, type, location, time, and cookie. A user on a Wire backend could use this endpoint to find registration time and location for each device for a given list of users. As a workaround, remove `/list-clients` from nginx config. This has been fixed in version 2021-03-02.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
- Fix · CNA wire-server (wireapp) Fixed in 2021-03-02
Timeline
- 2026-10-02 Threatist record created from CVE-2021-21396
References
More wireapp Wire Server vulnerabilities
- TI-2022-13166 Improper authentication in wireapp wire-server CVSS 3.1CRITICAL 9.8
- TI-2021-17943 CORS `Access-Control-Allow-Origin` settings are too lenient CVSS 3.1MEDIUM 5.7
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences