CVE-2022-37458 in Discourse
Summary
by MITRE • 09/02/2022
Discourse through 2.8.7 allows admins to send invitations to arbitrary email addresses at an unlimited rate.
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Analysis
by VulDB Data Team • 10/11/2022
The vulnerability identified as CVE-2022-37458 affects Discourse versions through 2.8.7 and represents a significant access control flaw that enables administrators to send invitations to any email address without restriction. This issue stems from inadequate validation mechanisms within the invitation system that fails to enforce proper authorization checks on recipient addresses. The flaw exists in the administrative functionality of the platform where invitation sending capabilities are not properly bounded by security controls, allowing malicious actors with administrative privileges to exploit this functionality for unauthorized email distribution.
The technical implementation of this vulnerability resides in the invitation processing logic where the system accepts arbitrary email addresses without performing proper validation against authorized recipient lists or rate limiting mechanisms. This represents a classic case of insufficient input validation and access control enforcement, aligning with CWE-284 which addresses improper access control vulnerabilities. The flaw specifically manifests when administrators attempt to send invitations through the administrative interface, where the system accepts any email address format without verification against legitimate user bases or security policies.
From an operational perspective, this vulnerability creates substantial risks including potential spamming campaigns, phishing attacks, and unauthorized user enumeration. Attackers with administrative access can leverage this flaw to flood arbitrary email addresses with invitations, potentially overwhelming target systems or using the invitations for social engineering purposes. The unlimited rate capability amplifies the impact, allowing rapid dissemination of invitations across multiple addresses without detection. This vulnerability directly impacts the platform's integrity and can be categorized under ATT&CK technique T1566 for social engineering and T1078 for valid accounts, as it enables unauthorized email distribution through legitimate administrative functions.
The mitigation strategy for CVE-2022-37458 requires immediate implementation of rate limiting controls and recipient validation mechanisms within the invitation system. Administrators should enforce strict validation of email addresses against known user bases and implement proper access controls to prevent unauthorized use of invitation functionality. The platform should be updated to version 2.8.8 or later where this vulnerability has been addressed through proper input validation and rate limiting. Organizations should also implement monitoring for unusual invitation patterns and establish proper administrative access controls to prevent unauthorized access to administrative functions. Additionally, security teams should review and enforce principle of least privilege for administrative accounts to minimize the potential impact of such vulnerabilities. The fix typically involves implementing proper email address validation, enforcing rate limits on invitation sending, and ensuring that administrative functions require proper authentication and authorization checks before execution.