Overview
CVE-2025-13033 is a high-severity vulnerability identified in an email parsing library. This flaw arises from improper handling of specially formatted recipient email addresses. A malicious actor can craft a recipient address containing an embedded external address within quotes, causing the application to misdirect emails to the attacker’s address instead of the legitimate internal recipient. This can result in significant data leaks, bypassing security filters and access controls, and unauthorized access to sensitive information.
Technical Details
The vulnerability occurs when the email parsing library fails to properly validate and sanitize recipient email addresses. An attacker can exploit this by crafting an address in the following format:
"attacker@example.com" <internal.recipient@example.org>Due to the parsing flaw, the email system interprets "attacker@example.com" as the intended recipient, effectively redirecting the email and any sensitive data it contains to the attacker’s control.
This flaw can exist in any application that uses the vulnerable email parsing library to process and route emails, including but not limited to:
- Web applications with contact forms
- Email marketing platforms
- Internal messaging systems
- Automated notification systems
CVSS Analysis
The vulnerability has a CVSS v3 score of 7.5 (HIGH).
This score reflects the significant impact this vulnerability can have, including the potential for data breaches and unauthorized access to sensitive information. The vulnerability is remotely exploitable and requires no user interaction.
Possible Impact
The exploitation of CVE-2025-13033 can lead to several severe consequences:
- Data Leakage: Sensitive information, including personal data, financial records, and confidential business communications, can be leaked to unauthorized parties.
- Bypassing Security Filters: Attackers can circumvent security measures like spam filters and access controls.
- Reputational Damage: A successful attack can damage an organization’s reputation and erode customer trust.
- Compliance Violations: Data breaches can lead to legal and regulatory penalties, especially if personal data is compromised.
- Internal Data Exposure: An attacker could get access to internal company emails, and other proprietary internal documents.
Mitigation and Patch Steps
To mitigate the risk associated with CVE-2025-13033, follow these steps:
- Update the Email Parsing Library: Upgrade to the latest version of the email parsing library that addresses the vulnerability. For Nodemailer users, update to a version that includes this commit.
- Input Validation: Implement strict input validation and sanitization for all recipient email addresses. Reject any addresses that contain suspicious characters or formatting.
- Email Address Verification: Verify the validity of email addresses before sending emails. This can involve checking the domain name and performing syntax checks.
- Security Audits: Conduct regular security audits of your applications to identify and address potential vulnerabilities.
- Web Application Firewalls (WAF): Employ a web application firewall to detect and block malicious requests targeting this vulnerability.
