CVE-2021-43963Network attack vector

Bucket write access via exposed stored credentials

Published Dec 7, 2021 · Updated Aug 4, 2024

Credential exposure in Couchbase Sync Gateway 2.7.0 through 2.8.2 allows remote authenticated users to obtain bucket write access. With shared bucket access enabled, Sync Gateway writes its Couchbase Server bucket credentials into sync-document metadata readable by users with bucket read access. The exposure requires shared bucket access and password-based server authentication; X.509 client-certificate deployments are unaffected.

CVSS severity8.1
High
EPSS probability0.50%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Credential exposure in Couchbase Sync Gateway 2.7.0 through 2.8.2 allows remote authenticated users to obtain bucket write access. With shared bucket access enabled, Sync Gateway writes its Couchbase Server bucket credentials into sync-document metadata readable by users with bucket read access. The exposure requires shared bucket access and password-based server authentication; X.509 client-certificate deployments are unaffected.

The record

CVE
CVE-2021-43963
Published
Dec 7, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-200, T1552
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 7, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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

5.5NIST National Vulnerability DatabaseAV:N/AC:L/Au:S/C:P/I:P/A:N
8.1NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-200Exposure of Sensitive Information to an Unauthorized Actor
T1552Unsecured Credentials

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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