A recently discovered vulnerability, CVE-2024-7208, affects multi-tenant email hosting services and exposes a critical security risk. This vulnerability enables an authenticated sender to spoof the identity of a shared, hosted domain—bypassing security measures like Domain-based Message Authentication, Reporting and Conformance (DMARC), Sender Policy Framework (SPF), and DomainKeys Identified Mail (DKIM) policies. The vulnerability has significant implications for organizations using shared hosting services, potentially allowing unauthorized users to send malicious emails apparently originating from a trusted domain.

Description of the Vulnerability

Multi-tenant hosting is a common architecture employed by email service providers (ESPs) that allows multiple organizations or users to share a single hosted domain. The inherent nature of this architecture requires that email security measures—such as DMARC, SPF, and DKIM—must be configured for each individual user or organization sharing the domain.

However, this newly identified vulnerability, CVE-2024-7208, permits an authenticated sender to exploit the multi-tenant hosting structure to send emails that appear to originate from another user or organization within the same hosted domain. This can create a false sense of trust in the email's contents, as it bypasses the security measures provided by DMARC, SPF, and DKIM.

Code Snippet

To illustrate this vulnerability, consider the following Python code snippet that demonstrates how an attacker can spoof the email address of another user or organization within a multi-tenant hosted domain:

import smtplib

from email.mime.text import MIMEText

# Attacker's email address
from_email = "attacker@example.com"
# Spoofed email address (belonging to another user or organization on the same hosted domain)
spoofed_email = "victim@example.com"
# Recipient's email address
to_email = "recipient@example.com"

message = MIMEText("This is a malicious email from a spoofed address.")
message["Subject"] = "Spoofed Email Demonstrating CVE-2024-7208 Vulnerability"
message["From"] = spoofed_email
message["To"] = to_email

smtp = smtplib.SMTP("mail.example.com")
smtp.login(from_email, "attacker_password")
smtp.sendmail(from_email, [to_email], message.as_string())
smtp.quit()

By manipulating the "From" field in the email headers, the attacker can create a forged email that seemingly comes from a domain within the hosted domain instead of their own email address. Consequently, email clients and recipients may perceive the malicious email as credible, increasing the risk of successful phishing or spear-phishing campaigns.

CVE-2024-7208: The vulnerability identifier.

- Link to original CVE report
- Affected systems: All multi-tenant hosting services that use DMARC, SPF, or DKIM for email authentication.
- DMARC: Official website
- SPF: Official website
- DKIM: Official website

Exploit Details & Mitigation

As of now, there is no direct patch for this vulnerability. Organizations must examine their multi-tenant hosting providers and ensure that proper authentication measures are in place to minimize the risk associated with CVE-2024-7208. Additionally, organizations should inform their users to be vigilant when receiving emails from shared hosted domains, emphasizing the importance of validating the source before acting on the email's content.

In Conclusion

CVE-2024-7208 is a critical vulnerability in multi-tenant hosting architectures that can provide cybercriminals with an opportunity to bypass security controls like DMARC, SPF, and DKIM. Users, organizations, and email service providers must remain vigilant about this security risk and ensure that appropriate measures are in place to mitigate the potential harm associated with this vulnerability.

Timeline

Published on: 07/30/2024 17:15:14 UTC
Last modified on: 10/29/2024 19:35:33 UTC