CVE-2021-41329 in Seq
Summary
by MITRE • 09/27/2021
Datalust Seq before 2021.2.6259 allows users (with view filters applied to their accounts) to see query results not constrained by their view filter. This information exposure, caused by an internal cache key collision, occurs when the user's view filter includes an array or IN clause, and when another user has recently executed an identical query differing only by the array elements.
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Analysis
by VulDB Data Team • 10/02/2021
This vulnerability affects Datalust Seq versions prior to 2021.2.6259 and represents a critical information exposure flaw that undermines the application's access control mechanisms. The vulnerability stems from an internal cache key collision issue that allows authenticated users to bypass view filter restrictions that should limit their visibility to specific query results. When users have view filters applied to their accounts, these filters are designed to constrain the data they can access, but the cache collision prevents proper enforcement of these restrictions.
The technical flaw manifests specifically when a user's view filter contains array or IN clause operations, which creates a scenario where the caching system fails to properly distinguish between different query executions. The vulnerability exploits a race condition in the internal caching mechanism where identical query patterns are treated as equivalent regardless of the specific array elements being queried. This collision occurs because the system uses a simplified cache key that does not adequately account for the varying array parameters within the same query structure, leading to improper cache hits that return unauthorized data.
The operational impact of this vulnerability is significant as it allows malicious or unauthorized users to potentially access sensitive data that should be restricted to specific user groups or roles. The exposure affects any user who has view filters configured with array or IN clauses, making it particularly dangerous in environments where data segregation is critical. Attackers could leverage this flaw to discover confidential information, potentially including personally identifiable information, business-sensitive data, or system-related details that should remain hidden from unauthorized personnel. The vulnerability essentially undermines the principle of least privilege by allowing data leakage across user boundaries.
This issue aligns with CWE-200, Information Exposure, and represents a specific implementation weakness in the caching system's key generation mechanism. From an ATT&CK perspective, this vulnerability maps to T1005, Data from Local System, and T1078, Valid Accounts, as it exploits legitimate user access to gain unauthorized data visibility. The vulnerability also demonstrates poor input validation and insufficient access control implementation, as the system fails to properly validate that cached query results match the requesting user's specific filter criteria. Organizations should implement immediate mitigations including upgrading to Seq version 2021.2.6259 or later, which contains the patched caching mechanism that properly differentiates cache keys based on array parameters. Additional defensive measures include reviewing and strengthening access control policies, monitoring for unusual query patterns, and implementing network segmentation to limit potential lateral movement if exploitation occurs.