CVE-2019-11465 in Couchbase Server
Summary
by MITRE
An issue was discovered in Couchbase Server 5.5.x through 5.5.3 and 6.0.0. The Memcached "connections" stat block command emits a non-redacted username. The system information submitted to Couchbase as part of a bug report included the usernames for all users currently logged into the system even if the log was redacted for privacy. This has been fixed (in 5.5.4 and 6.0.1) so that usernames are tagged properly in the logs and are hashed out when the logs are redacted.
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Analysis
by VulDB Data Team • 12/19/2023
The vulnerability identified as CVE-2019-11465 affects Couchbase Server versions 5.5.x through 5.5.3 and 6.0.0, representing a significant information disclosure weakness that undermines system security and privacy controls. This flaw manifests within the Memcached "connections" stat block command, where the system inadvertently exposes sensitive user authentication information through log files. The issue arises from improper handling of user credentials during system diagnostics and reporting processes, creating a vector for unauthorized information exposure that could compromise user accounts and system integrity.
The technical implementation of this vulnerability stems from inadequate redaction mechanisms within Couchbase Server's logging infrastructure. When system administrators or automated processes submit bug reports containing system information, the Memcached connections statistics include unfiltered username data from all active user sessions. This represents a failure in data sanitization and privacy protection protocols, where sensitive authentication information flows through system logs without proper obfuscation or removal. The flaw specifically impacts the memcached protocol implementation within Couchbase Server, where connection statistics are generated and subsequently logged without proper security filtering.
The operational impact of this vulnerability extends beyond simple information disclosure, potentially enabling credential harvesting attacks and unauthorized access attempts. Attackers could exploit this weakness to gather usernames of active system users, which combined with other reconnaissance data could facilitate targeted credential stuffing, brute force attacks, or social engineering campaigns. The vulnerability directly violates fundamental security principles by failing to implement proper access control and information flow protection mechanisms, creating a persistent risk for systems where Couchbase Server is deployed with user authentication requirements. This weakness particularly affects environments where multiple users maintain active connections and where system diagnostics are regularly submitted for support or monitoring purposes.
The remediation for CVE-2019-11465 involved implementing proper redaction protocols within Couchbase Server versions 5.5.4 and 6.0.1, where usernames are now appropriately tagged and hashed during log generation. This fix addresses the underlying issue by ensuring that sensitive user information is not exposed through system logging mechanisms, thereby protecting user privacy and system security. The solution aligns with established security practices for information sanitization and follows industry standards for protecting sensitive data in system logs, as outlined in CWE-200 (Information Exposure) and related security frameworks. Organizations should implement these updates immediately and conduct comprehensive security assessments to ensure proper implementation of log sanitization procedures. The vulnerability demonstrates the critical importance of proper data handling in system diagnostics and the necessity of robust privacy controls in all system components that may interact with sensitive user information.