CVE-2026-92716 in Shuffle
Summary
by MITRE • 09/16/2026
Shuffle through 2.2.1 contains a cross-tenant privilege escalation vulnerability in the HandleApiGeneration endpoint that allows administrators to reset and read API keys of non-administrator users in other organizations. Attackers with admin privileges in one organization can supply arbitrary user IDs to generate valid API keys for users in different organizations, enabling account takeover across tenant boundaries.
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Analysis
by VulDB Data Team • 09/16/2026
The vulnerability identified in Shuffle version 2.2.1 represents a critical cross-tenant privilege escalation flaw located within the HandleApiGeneration endpoint of the application's backend infrastructure. This security defect fundamentally undermines the isolation mechanisms designed to separate data and operational contexts between distinct organizational tenants. In multi-tenancy architectures, strict boundary enforcement is paramount to ensure that administrative actions performed by one tenant do not inadvertently or maliciously impact another. However, in this specific implementation, the logic governing API key generation fails to adequately validate whether the target user ID belongs to the same organization as the requesting administrator. This oversight allows an attacker with legitimate administrative privileges within their own organization to bypass these boundaries entirely.
From a technical perspective, the flaw stems from insufficient input validation and authorization checks on the HandleApiGeneration endpoint. When an authenticated administrator initiates a request to generate or reset an API key for a specific user ID, the system processes this request without verifying that the specified user ID is associated with the current tenant context. Consequently, if an attacker supplies arbitrary user IDs corresponding to users in other organizations, the backend logic proceeds to generate valid authentication tokens for those external accounts. This behavior effectively treats all user identifiers as globally accessible resources rather than restricting access to the local organizational scope. The ability to reset and read API keys is particularly dangerous because it grants full programmatic control over the targeted accounts without requiring knowledge of their passwords or multi-factor authentication credentials.
The operational impact of this vulnerability is severe, facilitating account takeover across tenant boundaries with minimal effort from an attacker who has already compromised a single administrative account within one organization. By leveraging this flaw, an adversary can gain unauthorized access to sensitive data, workflows, and integrations belonging to other organizations hosted on the same Shuffle instance. This breach not only compromises the confidentiality and integrity of external tenants but also exposes the service provider to significant liability and reputational damage due to a failure in maintaining multi-tenancy isolation standards. The ability to impersonate users across different entities can lead to further lateral movement, data exfiltration, or disruption of services for multiple unrelated organizations simultaneously.
This vulnerability aligns with CWE-269 Improper Privilege Management, specifically regarding the lack of proper authorization checks that allow a user to access resources belonging to another entity. It also maps directly to MITRE ATT&CK technique T1078 Valid Accounts, as it involves the misuse of legitimate credentials and privileges to gain unauthorized access. Furthermore, the cross-tenant nature of the attack relates to CWE-200 Information Exposure and CWE-640 Weak Password Recovery Mechanisms for Forgotten Passwords, given that API keys serve as primary authentication tokens similar to passwords. The exploitation path demonstrates a failure in enforcing logical access controls which are critical for secure multi-tenant applications.
To mitigate this vulnerability, immediate patching of Shuffle to version 2.2.1 or later is required, where the HandleApiGeneration endpoint has been updated to enforce strict tenant-scoped authorization checks. Developers must ensure that any operation involving user-specific resources includes a verification step confirming that the target resource belongs to the same organization as the requesting principal. Additionally, implementing robust input validation and context-aware access control lists can prevent similar issues in other endpoints. Security teams should also audit existing API key generation logs for signs of exploitation before applying patches and consider rotating keys for potentially affected users if there is evidence of unauthorized activity. Regular security assessments focusing on multi-tenancy isolation are recommended to identify and remediate such logical flaws proactively.