CVE-2013-4790 in AppSuite
Summary
by MITRE
Open-Xchange AppSuite before 7.0.2 rev14, 7.2.0 before rev11, 7.2.1 before rev10, and 7.2.2 before rev9 relies on user-supplied data to predict the IMAP server hostname for an external domain name, which allows remote authenticated users to discover e-mail credentials of other users in opportunistic circumstances via a manual-mode association of a personal e-mail address with the hostname of a crafted IMAP server.
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Analysis
by VulDB Data Team • 06/24/2024
The vulnerability described in CVE-2013-4790 represents a significant security flaw in Open-Xchange AppSuite email management software that affects multiple version ranges including 7.0.2 rev14, 7.2.0 rev11, 7.2.1 rev10, and 7.2.2 rev9. This issue stems from the application's improper handling of user-supplied data during IMAP server hostname prediction processes, creating a dangerous condition where authenticated users can exploit the system to gain unauthorized access to other users' email credentials. The vulnerability specifically manifests when the system attempts to associate a personal email address with an IMAP server hostname through a manual-mode configuration process, which should normally be a secure and controlled operation but becomes exploitable due to insufficient input validation and sanitization.
The technical flaw in this vulnerability can be categorized under CWE-20, which represents "Improper Input Validation," and more specifically aligns with CWE-287, "Improper Authentication." The system's reliance on user-supplied data for hostname prediction creates a path where malicious actors can manipulate the IMAP server hostname association process to target other users' credentials. When a user manually associates their email address with an IMAP server, the application should validate and sanitize all input parameters to ensure they originate from legitimate sources. However, the vulnerable implementation fails to properly validate the hostname data, allowing attackers to craft malicious IMAP server hostnames that can be used to extract credentials from other users' accounts. This vulnerability operates under the principle of privilege escalation through information disclosure, where authenticated users leverage their access to perform unauthorized credential harvesting.
The operational impact of this vulnerability extends beyond simple credential theft, as it enables a form of account takeover that can be executed with opportunistic timing and minimal technical expertise. Attackers can exploit this weakness to discover email credentials of other users within the same system, potentially leading to widespread compromise of email communications and associated data. The vulnerability is particularly concerning because it requires only authenticated access to the system, meaning that any user with legitimate credentials can potentially exploit this flaw to access other users' email accounts. This creates a scenario where malicious insiders or compromised accounts can escalate their privileges and access sensitive email communications, potentially leading to data breaches, phishing attacks, or further exploitation of the compromised email infrastructure. The opportunistic nature of this attack means that it can be executed at any time when the target user is manually configuring their email settings, making it difficult to detect and prevent.
Mitigation strategies for this vulnerability should focus on implementing robust input validation and sanitization mechanisms throughout the email configuration process, particularly when handling user-supplied IMAP server hostnames. Organizations should enforce strict hostname validation that ensures all input parameters are verified against known legitimate sources and reject any suspicious or malformed hostnames. The system should implement proper authentication checks to verify that users are only accessing their own email accounts and not attempting to associate other users' email addresses with malicious IMAP servers. Additionally, the application should implement rate limiting and monitoring mechanisms to detect unusual patterns of email configuration changes that might indicate exploitation attempts. From an ATT&CK framework perspective, this vulnerability maps to techniques involving credential access and privilege escalation, specifically targeting the T1566.001 sub-technique for credential access through credential dumping and T1078.004 for valid accounts. Organizations should also consider implementing network segmentation and access controls to limit the scope of potential exploitation, as well as regular security assessments to identify similar input validation vulnerabilities in other components of their email infrastructure. The vulnerability highlights the critical importance of secure coding practices and proper input validation in enterprise email systems to prevent exploitation of seemingly minor configuration flaws that can lead to significant security breaches.