What is CVE-2021-27925?

CVE-2021-27925 is a medium-severity vulnerability in Couchbase Server, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 4.4/10. Published 2021-05-19.

How severe is CVE-2021-27925?

Medium severity. CVSS v3 base score is 4.4 out of 10.

Vulnerability in Couchbase Server

CVE-2021-27925

An issue was discovered in Couchbase Server 6.5.x and 6.6.x through 6.6.1. When using the View Engine and Auditing is enabled, a crash condition can (depending on a race condition) cause an internal user with administrator privileges, @ns_server, to have its credentials leaked in cleartext in the ns_server.info.log file.

Vulnerability class: Race Condition

Published 2021-05-19 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.005 (42.5th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Couchbase Server

Weakness classification (CWE)

CWE-362 — Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition)

References

www.couchbase.com/resources/security (Vendor Advisory)
www.couchbase.com/downloads (Product, Vendor Advisory)

Frequently asked questions

What is CVE-2021-27925?: CVE-2021-27925 is a medium-severity vulnerability in Couchbase Server, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 4.4/10. Published 2021-05-19.
How severe is CVE-2021-27925?: Medium severity. CVSS v3 base score is 4.4 out of 10.