How severe is CVE-2019-11496?

CVE-2019-11496 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2019-11496 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-11496?

CVE-2019-11496 affects Couchbase Couchbase Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-11496?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2019-11496 published?

CVE-2019-11496 was published on 2019-09-10 and last updated on 2026-06-17.

CVE-2019-11496

CVE-2019-11496 is a critical-severity vulnerability in Couchbase Couchbase Server with a CVSS 3.x base score of 9.1. 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-306.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v2: 6.4
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Couchbase Couchbase Server
Published: 2019-09-10
Last modified: 2026-06-17

Description

In versions of Couchbase Server prior to 5.0, the bucket named "default" was a special bucket that allowed read and write access without authentication. As part of 5.0, the behavior of all buckets including "default" were changed to only allow access by authenticated users with sufficient authorization. However, users were allowed unauthenticated and unauthorized access to the "default" bucket if the properties of this bucket were edited. This has been fixed in versions 5.1.0 and 5.5.0.

Frequently asked questions

What is CVE-2019-11496?: In versions of Couchbase Server prior to 5.0, the bucket named "default" was a special bucket that allowed read and write access without authentication. As part of 5.0, the behavior of all buckets including "default" were changed to only allow access by authenticated users with sufficient authorization. However, users were allowed unauthenticated and unauthorized access to the "default" bucket if the properties of this bucket were edited. This has been fixed in versions 5.1.0 and 5.5.0.
How severe is CVE-2019-11496?: CVE-2019-11496 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2019-11496 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-11496?: CVE-2019-11496 affects Couchbase Couchbase Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-11496?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2019-11496 published?: CVE-2019-11496 was published on 2019-09-10 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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