VULNERABILITY INTELLIGENCE
CVE-2021-22538
CVSS score6.3 MEDIUM
EPSS probability0.72%
CISA KEVNot currently listed
Published2021-03-31
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
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.
Weakness classification
- CWE-20: Improper Input Validation
- CWE-276: Incorrect Default Permissions
Primary references
- cve-coordination@google.com — Patch, Third Party Advisory
- cve-coordination@google.com — Release Notes, Third Party Advisory
- cve-coordination@google.com — Release Notes, Third Party Advisory
- cve-coordination@google.com — Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Release Notes, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Release Notes, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory