CVE-2021-21396

Bulk list client endpoint exposes too much metadata about a client

Description

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.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.32%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: wireapp wire-server
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-21396?
CVE-2021-21396 has been scored as a medium severity vulnerability.
How to fix CVE-2021-21396?
To fix CVE-2021-21396, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21396 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21396 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21396?
CVE-2021-21396 affects wireapp wire-server.
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