CVE-2021-22538

Privilege escalation in RBAC system

Description

A privilege escalation vulnerability impacting the Google Exposure Notification Verification Server (versions prior to 0.23.1), allows an attacker who (1) has UserWrite permissions and (2) is using a carefully crafted request or malicious proxy, to create another user with higher privileges than their own. This occurs due to insufficient checks on the allowed set of permissions. The new user creation event would be captured in the Event Log.

Categories

6.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.24%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: Google LLC Exposure Notifications Verification Server
Published at:
Updated at:

References

Link Tags
https://github.com/google/exposure-notifications-verification-server/security/advisories/GHSA-5v95-v8c8-3rh6 third party advisory
https://github.com/google/exposure-notifications-verification-server/commit/eb8cf40b12dbe79304f1133c06fb73419383cd95 third party advisory patch
https://github.com/google/exposure-notifications-verification-server/releases/tag/v0.23.1 third party advisory release notes
https://github.com/google/exposure-notifications-verification-server/releases/tag/v0.24.0 third party advisory release notes

Frequently Asked Questions

What is the severity of CVE-2021-22538?
CVE-2021-22538 has been scored as a medium severity vulnerability.
How to fix CVE-2021-22538?
To fix CVE-2021-22538, 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-2021-22538 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-22538 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-2021-22538?
CVE-2021-22538 affects Google LLC Exposure Notifications Verification Server.
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