CVE-2024-27101 in spicedb
Summary
by MITRE • 03/01/2024
SpiceDB is an open source, Google Zanzibar-inspired database for creating and managing security-critical application permissions. Integer overflow in chunking helper causes dispatching to miss elements or panic. Any SpiceDB cluster with any schema where a resource being checked has more than 65535 relationships for the same resource and subject type is affected by this problem. The CheckPermission, BulkCheckPermission, and LookupSubjects API methods are affected. This vulnerability is fixed in 1.29.2.
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Analysis
by VulDB Data Team • 09/03/2025
The vulnerability identified as CVE-2024-27101 affects SpiceDB, an open-source database system designed for managing application permissions using a Google Zanzibar-inspired architecture. This system serves as a critical component for security-critical applications requiring fine-grained access control and permission management. The flaw manifests as an integer overflow within the chunking helper functionality that governs how relationships are processed and dispatched within the database. This issue specifically impacts clusters where resources possess more than 65535 relationships for the same resource and subject type combination, creating a scenario where the system's internal arithmetic operations exceed their maximum representable values.
The technical implementation of this vulnerability stems from improper handling of integer values during the chunking process that divides large datasets for processing. When the system encounters relationship sets exceeding 65535 entries for identical resource and subject type combinations, the integer overflow causes the chunking algorithm to miscalculate boundaries and offsets. This failure results in elements being skipped during processing or system panics that terminate operations. The affected API methods include CheckPermission, BulkCheckPermission, and LookupSubjects, which represent core functionality for permission evaluation and subject lookup operations. The vulnerability is classified under CWE-191 Integer Underflow/Overflow, specifically manifesting as an integer overflow condition that affects the proper dispatching of relationship data.
The operational impact of this vulnerability extends beyond simple performance degradation to potentially compromise security integrity within affected systems. When elements are missed during dispatching, it creates gaps in permission evaluation that could allow unauthorized access to resources that should be restricted. The system panic conditions introduce reliability issues that may affect availability and could be exploited by malicious actors to disrupt service operations. Organizations relying on SpiceDB for critical access control decisions face potential security breaches where permission checks may fail to properly validate access rights. The vulnerability affects any deployment where the specified relationship threshold is exceeded, making it particularly concerning for systems with high-volume relationship data or complex permission structures.
Mitigation strategies for CVE-2024-27101 require immediate deployment of SpiceDB version 1.29.2, which contains the necessary patches to resolve the integer overflow condition. System administrators should conduct thorough testing of their permission schemas to identify resources that exceed the 65535 relationship threshold, as these represent the highest risk scenarios. Organizations should implement monitoring solutions to detect unusual patterns in API call failures or system panics that might indicate exploitation attempts. The vulnerability aligns with ATT&CK technique T1566.002 for credential access through privilege escalation and represents a potential pathway for attackers to bypass access controls. Security teams should also consider implementing rate limiting and additional validation checks for permission evaluation APIs to reduce the impact of any potential exploitation attempts. Regular schema reviews and relationship count monitoring should become standard practices to prevent similar issues in the future.