How severe is CVE-2021-27924?

CVE-2021-27924 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-27924 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27924?

CVE-2021-27924 affects Couchbase Couchbase Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27924?

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

When was CVE-2021-27924 published?

CVE-2021-27924 was published on 2021-05-19 and last updated on 2026-06-17.

CVE-2021-27924

CVE-2021-27924 is a medium-severity vulnerability in Couchbase Couchbase Server with a CVSS 3.x base score of 5.9. 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 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-319
Affected product: Couchbase Couchbase Server
Published: 2021-05-19
Last modified: 2026-06-17

Description

An issue was discovered in Couchbase Server 6.x through 6.6.1. The Couchbase Server UI is insecurely logging session cookies in the logs. This allows for the impersonation of a user if the log files are obtained by an attacker before a session cookie expires.

Frequently asked questions

What is CVE-2021-27924?: An issue was discovered in Couchbase Server 6.x through 6.6.1. The Couchbase Server UI is insecurely logging session cookies in the logs. This allows for the impersonation of a user if the log files are obtained by an attacker before a session cookie expires.
How severe is CVE-2021-27924?: CVE-2021-27924 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-27924 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27924?: CVE-2021-27924 affects Couchbase Couchbase Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27924?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-27924 published?: CVE-2021-27924 was published on 2021-05-19 and last updated on 2026-06-17.

References

Affected products (1)

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

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