CVE-2024-52508 in Mail
Summary
by MITRE • 11/15/2024
Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. When a user is trying to set up a mail account with an email address like [email protected] that does not support auto configuration, and an attacker managed to register autoconfig.tld, the used email details would be send to the server of the attacker. It is recommended that the Nextcloud Mail app is upgraded to 1.14.6, 1.15.4, 2.2.11, 3.6.3, 3.7.7 or 4.0.0.
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Analysis
by VulDB Data Team • 10/01/2025
The vulnerability identified as CVE-2024-52508 affects Nextcloud Mail, a critical component of the Nextcloud self-hosted productivity platform that enables users to manage email accounts within their decentralized infrastructure. This security flaw represents a significant concern for organizations relying on Nextcloud for their communication needs, as it exposes user email configuration data to potential attackers through a specific configuration mechanism. The vulnerability manifests when users attempt to configure email accounts using addresses that lack native auto-configuration support, creating a pathway for data exfiltration that directly impacts the confidentiality and integrity of email communications within the Nextcloud environment.
The technical implementation of this vulnerability stems from the mail application's handling of email auto-configuration requests when standard autoconfig.tld domains are not available. When a user attempts to set up an email account with an address like [email protected] that doesn't support auto-configuration, the system falls back to attempting to resolve autoconfig.tld, which could be controlled by an attacker who has registered this domain. This creates an opportunity for man-in-the-middle attacks where email account details, including potentially sensitive authentication credentials, are inadvertently transmitted to the attacker's server instead of the legitimate mail server. The flaw essentially represents a DNS-based redirection vulnerability where the application fails to properly validate the destination of auto-configuration requests, allowing for arbitrary server redirection.
The operational impact of this vulnerability extends beyond simple data leakage, as it represents a critical failure in the authentication and authorization mechanisms of the Nextcloud Mail application. Attackers can exploit this vulnerability to harvest email account configurations from unsuspecting users, potentially gaining access to multiple email accounts and compromising the broader security posture of organizations using Nextcloud. The vulnerability affects multiple versions of the Nextcloud Mail application, including 1.x, 2.x, 3.x, and 4.x series, indicating a widespread exposure across the product lifecycle. This issue directly violates security principles related to secure communication and data protection, as outlined in CWE-200 (Information Exposure) and CWE-310 (Cryptographic Issues), and aligns with ATT&CK technique T1566 (Phishing) and T1071.004 (Application Layer Protocol: DNS) in the MITRE ATT&CK framework.
Organizations should immediately upgrade their Nextcloud Mail installations to versions 1.14.6, 1.15.4, 2.2.11, 3.6.3, 3.7.7, or 4.0.0 to remediate this vulnerability. The upgrade process should be coordinated with existing security protocols to ensure that no additional exposure occurs during the transition period. Additionally, system administrators should conduct comprehensive audits of their email configuration processes and implement monitoring for suspicious DNS resolution patterns. Network security controls should be enhanced to detect and block unauthorized auto-configuration requests, while user education programs should emphasize the importance of verifying email account setup procedures. The vulnerability serves as a reminder of the critical importance of proper input validation and secure DNS resolution practices in web applications, particularly those handling sensitive authentication data within enterprise environments.