High severity · published Dec 7, 2021
CVE-2021-43963
An issue was discovered in Couchbase Sync Gateway 2.7.0 through 2.8.2
8.1
CVSS
0.5%
EPSS
No
On KEV
Description
An issue was discovered in Couchbase Sync Gateway 2.7.0 through 2.8.2. The bucket credentials used to read and write data in Couchbase Server were insecurely being stored in the metadata within sync documents written to the bucket. Users with read access could use these credentials to obtain write access. (This issue does not affect clusters where Sync Gateway is authenticated with X.509 client certificates. This issue also does not affect clusters where shared bucket access is not enabled on Sync Gateway.)
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SG
Sync Gateway · Couchbase
2.7.0 before 2.8.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-43963
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-43963
Vendor Advisory
https://www.couchbase.com/alerts
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