How severe is CVE-2020-1955?

CVE-2020-1955 has a CVSS 3.x base score of 9.8, 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 high.

Is CVE-2020-1955 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-1955?

CVE-2020-1955 affects Apache Couchdb. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-1955?

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-2020-1955 published?

CVE-2020-1955 was published on 2020-05-20 and last updated on 2026-06-17.

CVE-2020-1955

CVE-2020-1955 is a critical-severity vulnerability in Apache Couchdb with a CVSS 3.x base score of 9.8. 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 9.8)
CVSS v2: 6.8
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Apache Couchdb
Published: 2020-05-20
Last modified: 2026-06-17

Description

CouchDB version 3.0.0 shipped with a new configuration setting that governs access control to the entire database server called `require_valid_user_except_for_up`. It was meant as an extension to the long standing setting `require_valid_user`, which in turn requires that any and all requests to CouchDB will have to be made with valid credentials, effectively forbidding any anonymous requests. The new `require_valid_user_except_for_up` is an off-by-default setting that was meant to allow requiring valid credentials for all endpoints except for the `/_up` endpoint. However, the implementation of this made an error that lead to not enforcing credentials on any endpoint, when enabled. CouchDB versions 3.0.1[1] and 3.1.0[2] fix this issue.

Frequently asked questions

What is CVE-2020-1955?: CouchDB version 3.0.0 shipped with a new configuration setting that governs access control to the entire database server called `require_valid_user_except_for_up`. It was meant as an extension to the long standing setting `require_valid_user`, which in turn requires that any and all requests to CouchDB will have to be made with valid credentials, effectively forbidding any anonymous requests. The new `require_valid_user_except_for_up` is an off-by-default setting that was meant to allow requiring valid credentials for all endpoints except for the `/_up` endpoint. However, the implementation of this made an error that lead to not enforcing credentials on any endpoint, when enabled. CouchDB versions 3.0.1[1] and 3.1.0[2] fix this issue.
How severe is CVE-2020-1955?: CVE-2020-1955 has a CVSS 3.x base score of 9.8, 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 high.
Is CVE-2020-1955 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-1955?: CVE-2020-1955 affects Apache Couchdb. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-1955?: 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-2020-1955 published?: CVE-2020-1955 was published on 2020-05-20 and last updated on 2026-06-17.

References

https://docs.couchdb.org/en/master/cve/2020-1955.html

Affected products (1)

cpe:2.3:a:apache:couchdb:3.0.0:*:*:*:*:*:*:*

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