CVE-2021-31158Network attack vector

Unauthorized data reads via CTE permission bypass

Published May 19, 2021 · Updated Aug 3, 2024

Incorrect authorization in Couchbase Server 6.5.0 through 6.5.2 and 6.6.0 through 6.6.1 allows remote authenticated users to read restricted data. The Query Engine processes N1QL Common Table Expression queries without correctly enforcing the requesting user's RBAC permissions, so a query can reach resources outside the assigned authorization scope. A valid low-privilege account and network access to the query service are required; the documented consequence is unauthorized read access only.

CVSS severity6.5
Medium
EPSS probability0.70%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect authorization in Couchbase Server 6.5.0 through 6.5.2 and 6.6.0 through 6.6.1 allows remote authenticated users to read restricted data. The Query Engine processes N1QL Common Table Expression queries without correctly enforcing the requesting user's RBAC permissions, so a query can reach resources outside the assigned authorization scope. A valid low-privilege account and network access to the query service are required; the documented consequence is unauthorized read access only.

The record

CVE
CVE-2021-31158
Published
May 19, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-863, T1213
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 19, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
4.0NIST NVDAV:N/AC:L/Au:S/C:P/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-863Incorrect Authorization
T1213Data from Information Repositories

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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