How severe is CVE-2021-25643?

CVE-2021-25643 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-25643 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (39th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-25643?

CVE-2021-25643 affects Couchbase Couchbase Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-25643?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-25643 published?

CVE-2021-25643 was published on 2021-05-26 and last updated on 2026-06-17.

CVE-2021-25643

CVE-2021-25643 is a medium-severity vulnerability in Couchbase Couchbase Server with a CVSS 3.x base score of 4.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-319.

Key facts

Severity: Medium (CVSS 3.x base score 4.9)
CVSS v2: 4.0
EPSS exploit prediction: 1% (39th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-319
Affected product: Couchbase Couchbase Server
Published: 2021-05-26
Last modified: 2026-06-17

Description

An issue was discovered in Couchbase Server 5.x and 6.x before 6.5.2 and 6.6.x before 6.6.2. Internal users with administrator privileges, @cbq-engine-cbauth and @index-cbauth, leak credentials in cleartext in the indexer.log file when they make a /listCreateTokens, /listRebalanceTokens, or /listMetadataTokens call.

Frequently asked questions

What is CVE-2021-25643?: An issue was discovered in Couchbase Server 5.x and 6.x before 6.5.2 and 6.6.x before 6.6.2. Internal users with administrator privileges, @cbq-engine-cbauth and @index-cbauth, leak credentials in cleartext in the indexer.log file when they make a /listCreateTokens, /listRebalanceTokens, or /listMetadataTokens call.
How severe is CVE-2021-25643?: CVE-2021-25643 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-25643 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (39th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-25643?: CVE-2021-25643 affects Couchbase Couchbase Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-25643?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-25643 published?: CVE-2021-25643 was published on 2021-05-26 and last updated on 2026-06-17.

References

https://www.couchbase.com/resources/security#SecurityAlerts

Affected products (1)

cpe:2.3:a:couchbase:couchbase_server:*:*:*:*:*:*:*:*

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